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Sample records for advanced electrical materials

  1. Advanced Electrical Materials and Component Development

    NASA Technical Reports Server (NTRS)

    Schwarze, Gene E.

    2003-01-01

    The primary means to develop advanced electrical components is to develop new and improved materials for magnetic components (transformers, inductors, etc.), capacitors, and semiconductor switches and diodes. This paper will give a description and status of the internal and external research sponsored by NASA Glenn Research Center on soft magnetic materials, dielectric materials and capacitors, and high quality silicon carbide (SiC) atomically smooth substrates. The rationale for and the benefits of developing advanced electrical materials and components for the PMAD subsystem and also for the total power system will be briefly discussed.

  2. Advanced Electrical Materials and Components Being Developed

    NASA Technical Reports Server (NTRS)

    Schwarze, Gene E.

    2004-01-01

    All aerospace systems require power management and distribution (PMAD) between the energy and power source and the loads. The PMAD subsystem can be broadly described as the conditioning and control of unregulated power from the energy source and its transmission to a power bus for distribution to the intended loads. All power and control circuits for PMAD require electrical components for switching, energy storage, voltage-to-current transformation, filtering, regulation, protection, and isolation. Advanced electrical materials and component development technology is a key technology to increasing the power density, efficiency, reliability, and operating temperature of the PMAD. The primary means to develop advanced electrical components is to develop new and/or significantly improved electronic materials for capacitors, magnetic components, and semiconductor switches and diodes. The next important step is to develop the processing techniques to fabricate electrical and electronic components that exceed the specifications of presently available state-of-the-art components. The NASA Glenn Research Center's advanced electrical materials and component development technology task is focused on the following three areas: 1) New and/or improved dielectric materials for the development of power capacitors with increased capacitance volumetric efficiency, energy density, and operating temperature; 2) New and/or improved high-frequency, high-temperature soft magnetic materials for the development of transformers and inductors with increased power density, energy density, electrical efficiency, and operating temperature; 3) Packaged high-temperature, high-power density, high-voltage, and low-loss SiC diodes and switches.

  3. Advanced Electrical Materials and Components Development: An Update

    NASA Technical Reports Server (NTRS)

    Schwarze, Gene E.

    2005-01-01

    The primary means to develop advanced electrical components is to develop new and improved materials for magnetic components (transformers, inductors, etc.), capacitors, and semiconductor switches and diodes. This paper will give an update of the Advanced Power Electronics and Components Technology being developed by the NASA Glenn Research Center for use in future Power Management and Distribution subsystems used in space power systems for spacecraft and lunar and planetary surface power. The initial description and status of this technology program was presented two years ago at the First International Energy Conversion Engineering Conference held at Portsmouth, Virginia, August 2003. The present paper will give a brief background of the previous work reported and a summary of research performed the past several years on soft magnetic materials characterization, dielectric materials and capacitor developments, high quality silicon carbide atomically smooth substrates, and SiC static and dynamic device characterization under elevated temperature conditions. The rationale for and the benefits of developing advanced electrical materials and components for the PMAD subsystem and also for the total power system will also be briefly discussed.

  4. ADVANCED ELECTRIC AND MAGNETIC MATERIAL MODELS FOR FDTD ELECTROMAGNETIC CODES

    SciTech Connect

    Poole, B R; Nelson, S D; Langdon, S

    2005-05-05

    The modeling of dielectric and magnetic materials in the time domain is required for pulse power applications, pulsed induction accelerators, and advanced transmission lines. For example, most induction accelerator modules require the use of magnetic materials to provide adequate Volt-sec during the acceleration pulse. These models require hysteresis and saturation to simulate the saturation wavefront in a multipulse environment. In high voltage transmission line applications such as shock or soliton lines the dielectric is operating in a highly nonlinear regime, which require nonlinear models. Simple 1-D models are developed for fast parameterization of transmission line structures. In the case of nonlinear dielectrics, a simple analytic model describing the permittivity in terms of electric field is used in a 3-D finite difference time domain code (FDTD). In the case of magnetic materials, both rate independent and rate dependent Hodgdon magnetic material models have been implemented into 3-D FDTD codes and 1-D codes.

  5. Outdoor testing of advanced optical materials for solar thermal electric applications

    NASA Astrophysics Data System (ADS)

    Wendelin, T. J.; Jorgensen, G.; Goggin, R. M.

    1992-05-01

    The development of low-cost, durable advanced optical materials is an important element in making solar energy viable for electricity production. It is important to determine the expected lifetime of candidate reflector materials in real-world service conditions. The demonstration of the optical durability of such materials in outdoor environments is critical to the successful commercialization of solar thermal electric technologies. For many years, optical performance data have been collected and analyzed by the National Renewable Energy Laboratory (NREL) for candidate reflector materials subjected to simulated outdoor exposure conditions. Much of this testing is accelerated in order to predict service durability. Some outdoor testing has occurred, but not in a systematic manner. To date, simulated/accelerated testing has had limited correlation with actual outdoor exposure testing. Such a correlation is desirable to provide confidence in lifetime predictions based upon accelerated weathering methods. To obtain outdoor exposure data for realistic environments and to establish a data base for correlating simulated/accelerated outdoor exposure data with actual outdoor exposure data, the development of an expanded outdoor testing program has recently been initiated by NREL. Several outdoor test sites will be selected based on the solar climate, potential for solar energy utilization by industry, and cost of installation. Test results are site dependent because exposure conditions vary with geographical location. The importance of this program to optical materials development is outlined, and the process used to determine and establish the outdoor test sites is described. Candidate material identification and selection is also discussed.

  6. Outdoor testing of advanced optical materials for solar thermal electric applications

    SciTech Connect

    Wendelin, T.J.; Jorgensen, G.; Goggin, R.M.

    1992-05-01

    The development of low-cost, durable advanced optical materials is an important element in making solar energy viable for electricity production. It is important to determine the expected lifetime of candidate reflector materials in real-world service conditions. The demonstration of the optical durability of such materials in outdoor environments is critical to the successful commercialization of solar thermal electric technologies. For many years optical performance data have been collected and analyzed by the National Renewable Energy Laboratory (NREL) for candidate reflector materials subjected to simulated outdoor exposure conditions. Much of this testing is accelerated in order to predict service durability. Some outdoor testing has occurred but not in a systematic manner. To date, simulated/accelerated testing has been limited correlation with actual outdoor exposure testing. Such a correlation is desirable to provide confidence in lifetime predictions based upon accelerated weathering methods. To obtain outdoor exposure data for realistic environments and to establish a data base for correlating simulated/accelerated outdoor exposure data with actual outdoor exposure data, the development of an expanded outdoor testing program has recently been initiated by NREL. Several outdoor test sites will be selected based on the solar climate, potential for solar energy utilization by industry, and cost of installation. Test results are site dependent because exposure conditions vary with geographical location. The importance of this program to optical materials development is outlined, and the process used to determine and establish the outdoor test sites is described. Candidate material identification and selection is also discussed. 10 refs.

  7. Advanced electric vehicle

    SciTech Connect

    O'Connell, L.G.

    1980-07-01

    The Advanced Electric Vehicle is defined as an automobile which can fulfill the general-purpose role of today's internal-combustion-engine-powered car without utilizing petroleum fuels directly. It relies principally on the utilization of electricity. A number of candidate systems are described. The present status of each is discussed as are the problems to be overcome before implementation can proceed.

  8. Drafting. Advanced Print Reading--Electrical.

    ERIC Educational Resources Information Center

    Oregon State Dept. of Education, Salem.

    This document is a workbook for drafting students learning advanced print reading for electricity applications. The workbook contains seven units covering the following material: architectural working drawings; architectural symbols and dimensions; basic architectural electrical symbols; wiring symbols; riser diagrams; schematic diagrams; and…

  9. Electrically conductive material

    DOEpatents

    Singh, J.P.; Bosak, A.L.; McPheeters, C.C.; Dees, D.W.

    1993-09-07

    An electrically conductive material is described for use in solid oxide fuel cells, electrochemical sensors for combustion exhaust, and various other applications possesses increased fracture toughness over available materials, while affording the same electrical conductivity. One embodiment of the sintered electrically conductive material consists essentially of cubic ZrO[sub 2] as a matrix and 6-19 wt. % monoclinic ZrO[sub 2] formed from particles having an average size equal to or greater than about 0.23 microns. Another embodiment of the electrically conductive material consists essentially at cubic ZrO[sub 2] as a matrix and 10-30 wt. % partially stabilized zirconia (PSZ) formed from particles having an average size of approximately 3 microns. 8 figures.

  10. Electrically conductive material

    DOEpatents

    Singh, Jitendra P.; Bosak, Andrea L.; McPheeters, Charles C.; Dees, Dennis W.

    1993-01-01

    An electrically conductive material for use in solid oxide fuel cells, electrochemical sensors for combustion exhaust, and various other applications possesses increased fracture toughness over available materials, while affording the same electrical conductivity. One embodiment of the sintered electrically conductive material consists essentially of cubic ZrO.sub.2 as a matrix and 6-19 wt. % monoclinic ZrO.sub.2 formed from particles having an average size equal to or greater than about 0.23 microns. Another embodiment of the electrically conductive material consists essentially at cubic ZrO.sub.2 as a matrix and 10-30 wt. % partially stabilized zirconia (PSZ) formed from particles having an average size of approximately 3 microns.

  11. Advances in dental materials.

    PubMed

    Vaderhobli, Ram M

    2011-07-01

    The use of materials to rehabilitate tooth structures is constantly changing. Over the past decade, newer material processing techniques and technologies have significantly improved the dependability and predictability of dental material for clinicians. The greatest obstacle, however, is in choosing the right combination for continued success. Finding predictable approaches for successful restorative procedures has been the goal of clinical and material scientists. This article provides a broad perspective on the advances made in various classes of dental restorative materials in terms of their functionality with respect to pit and fissure sealants, glass ionomers, and dental composites. PMID:21726695

  12. Electrically conductive composite material

    DOEpatents

    Clough, Roger L.; Sylwester, Alan P.

    1989-01-01

    An electrically conductive composite material is disclosed which comprises a conductive open-celled, low density, microcellular carbon foam filled with a non-conductive polymer or resin. The composite material is prepared in a two-step process consisting of first preparing the microcellular carbon foam from a carbonizable polymer or copolymer using a phase separation process, then filling the carbon foam with the desired non-conductive polymer or resin. The electrically conductive composites of the present invention has a uniform and consistant pattern of filler distribution, and as a result is superior over prior art materials when used in battery components, electrodes, and the like.

  13. Electrically conductive composite material

    DOEpatents

    Clough, R.L.; Sylwester, A.P.

    1988-06-20

    An electrically conductive composite material is disclosed which comprises a conductive open-celled, low density, microcellular carbon foam filled with a non-conductive polymer or resin. The composite material is prepared in a two-step process consisting of first preparing the microcellular carbon foam from a carbonizable polymer or copolymer using a phase separation process, then filling the carbon foam with the desired non-conductive polymer or resin. The electrically conductive composites of the present invention has a uniform and consistent pattern of filler distribution, and as a result is superior over prior art materials when used in battery components, electrodes, and the like. 2 figs.

  14. Advanced materials for energy storage.

    PubMed

    Liu, Chang; Li, Feng; Ma, Lai-Peng; Cheng, Hui-Ming

    2010-02-23

    Popularization of portable electronics and electric vehicles worldwide stimulates the development of energy storage devices, such as batteries and supercapacitors, toward higher power density and energy density, which significantly depends upon the advancement of new materials used in these devices. Moreover, energy storage materials play a key role in efficient, clean, and versatile use of energy, and are crucial for the exploitation of renewable energy. Therefore, energy storage materials cover a wide range of materials and have been receiving intensive attention from research and development to industrialization. In this Review, firstly a general introduction is given to several typical energy storage systems, including thermal, mechanical, electromagnetic, hydrogen, and electrochemical energy storage. Then the current status of high-performance hydrogen storage materials for on-board applications and electrochemical energy storage materials for lithium-ion batteries and supercapacitors is introduced in detail. The strategies for developing these advanced energy storage materials, including nanostructuring, nano-/microcombination, hybridization, pore-structure control, configuration design, surface modification, and composition optimization, are discussed. Finally, the future trends and prospects in the development of advanced energy storage materials are highlighted. PMID:20217798

  15. Advanced electrical power system technology for the all electric aircraft

    NASA Technical Reports Server (NTRS)

    Finke, R. C.; Sundberg, G. R.

    1983-01-01

    The application of advanced electric power system technology to an all electric airplane results in an estimated reduction of the total takeoff gross weight of over 23,000 pounds for a large airplane. This will result in a 5 to 10 percent reduction in direct operating costs (DOC). Critical to this savings is the basic electrical power system component technology. These advanced electrical power components will provide a solid foundation for the materials, devices, circuits, and subsystems needed to satisfy the unique requirements of advanced all electric aircraft power systems. The program for the development of advanced electrical power component technology is described. The program is divided into five generic areas: semiconductor devices (transistors, thyristors, and diodes); conductors (materials and transmission lines); dielectrics; magnetic devices; and load management devices. Examples of progress in each of the five areas are discussed. Bipolar power transistors up to 1000 V at 100 A with a gain of 10 and a 0.5 microsec rise and fall time are presented. A class of semiconductor devices with a possibility of switching up to 100 kV is described. Solid state power controllers for load management at 120 to 1000 V and power levels to 25 kW were developed along with a 25 kW, 20 kHz transformer weighing only 3.2 kg.

  16. Advanced electrical power system technology for the all electric aircraft

    NASA Technical Reports Server (NTRS)

    Finke, R. C.; Sundberg, G. R.

    1983-01-01

    The application of advanced electric power system technology to an all electric airplane results in an estimated reduction of the total takeoff gross weight of over 23,000 pounds for a large airplane. This will result in a 5 to 10 percent reduction in direct operating costs (DOC). Critical to this savings is the basic electrical power system component technology. These advanced electrical power components will provide a solid foundation for the materials, devices, circuits, and subsystems needed to satisfy the unique requirements of advanced all electric aircraft power systems. The program for the development of advanced electrical power component technology is described. The program is divided into five generic areas: semiconductor devices (transistors, thyristors, and diodes); conductors (materials and transmission lines); dielectrics; magnetic devices; and load management devices. Examples of progress in each of the five areas are discussed. Bipolar power transistors up to 1000 V at 100 A with a gain of 10 and a 0.5 microsec rise and fall time are presented. A class of semiconductor devices with a possibility of switching up to 100 kV is described. Solid state power controllers for load management at 120 to 1000 V and power levels to 25 kW were developed along with a 25 kW, 20 kHz transformer weighing only 3.2 kg. Previously announced in STAR as N83-24764

  17. Advanced desiccant materials research

    NASA Astrophysics Data System (ADS)

    Czanderna, A. W.; Thomas, T. M.

    1986-05-01

    The long-range goal of this task is to understand the role of surface phenomena in desiccant cooling materials. The background information includes a brief introduction to desiccant cooling systems (DCS) and the role of the desiccant as a system component. The purpose, background, rationale, and long-term technical approach for studying advanced desiccant materials are then treated. Experimental methods for measuring water vapor sorption by desiccants are described, and the rationale is then given for choosing a quartz crystal microbalance (QCM) for measuring sorption isotherms, rates, and cyclic stability. Background information is given about the QCM, including the quartz crystal resonator itself, the support structure for the quartz crystal, and the advantages and limitations of a QCM. The apparatus assembled and placed into operation during CY 1985 is described. The functions of the principal components of the equipment, i.e., the QCM, vacuum system, pressure gauges, residual gas analyzer, constant temperature bath, and data acquisition system, are described as they relate to the water vapor sorption measurements now under way. The criteria for narrowing the potential candidates as advanced desiccant materials for the initial studies are given. Also given is a list of 20 principal candidate materials identified based on the criteria and data available in the literature.

  18. Accelerating advanced-materials commercialization

    NASA Astrophysics Data System (ADS)

    Maine, Elicia; Seegopaul, Purnesh

    2016-05-01

    Long commercialization times, high capital costs and sustained uncertainty deter investment in innovation for advanced materials. With appropriate strategies, technology and market uncertainties can be reduced, and the commercialization of advanced materials accelerated.

  19. Advanced composite materials and processes

    NASA Technical Reports Server (NTRS)

    Baucom, Robert M.

    1991-01-01

    Composites are generally defined as two or more individual materials, which, when combined into a single material system, results in improved physical and/or mechanical properties. The freedom of choice of the starting components for composites allows the generation of materials that can be specifically tailored to meet a variety of applications. Advanced composites are described as a combination of high strength fibers and high performance polymer matrix materials. These advanced materials are required to permit future aircraft and spacecraft to perform in extended environments. Advanced composite precursor materials, processes for conversion of these materials to structures, and selected applications for composites are reviewed.

  20. Materials for advanced batteries

    SciTech Connect

    Murphy, D.W.; Broadhead, J.

    1980-01-01

    The requirements of battery systems are considered along with some recent studies of materials of importance in aqueous electrochemical energy-storage systems, lithium-aluminum/iron sulfide batteries, solid electrolytes, molten salt electrolytes in secondary batteries, the recharging of the lithium electrode in organic electrolytes, intercalation electrodes, and interface phenomena in advanced batteries. Attention is given to a lead-acid battery overview, the design and development of micro-reference electrodes for the lithium/metal-sulfide cell system, molten salt electrochemical studies and high energy density cell development, a selenium (IV) cathode in molten chloroaluminates, and the behavior of hard and soft ions in solid electrolytes. Other topics explored are related to the use of the proton conductor hydrogen uranyl phosphate tetrahydrate as the solid electrolyte in hydride-air batteries and hydrogen-oxygen fuel cells, the behavior of the passivating film in Li/SOCl2 cells under various conditions, and the analysis of surface insulating films in lithium nitride crystals.

  1. Advanced batteries for electric vehicles

    SciTech Connect

    Henriksen, G.L.; DeLuca, W.H.; Vissers, D.R. )

    1994-11-01

    The idea of battery-powered vehicles is an old one that took on new importance during the oil crisis of 1973 and after California passed laws requiring vehicles that would produce no emissions (so-called zero-emission vehicles). In this overview of battery technologies, the authors review the major existing or near-term systems as well as advanced systems being developed for electric vehicle (EV) applications. However, this overview does not cover all the advanced batteries being developed currently throughout the world. Comparative characteristics for the following batteries are given: lead-acid; nickel/cadmium; nickel/iron; nickel/metal hydride; zinc/bromine; sodium/sulfur; sodium/nickel chloride; zinc/air; lithium/iron sulfide; and lithium-polymer.

  2. New Advanced Dielectric Materials for Accelerator Applications

    SciTech Connect

    Kanareykin, A.

    2010-11-04

    We present our recent results on the development and experimental testing of advanced dielectric materials that are capable of supporting the high RF electric fields generated by electron beams or pulsed high power microwaves. These materials have been optimized or specially designed for accelerator applications. The materials discussed here include low loss microwave ceramics, quartz, Chemical Vapor Deposition diamonds and nonlinear Barium Strontium Titanate based ferroelectrics.

  3. Advanced Electric Traction System Technology Development

    SciTech Connect

    Anderson, Iver

    2011-01-14

    As a subcontractor to General Motors (GM), Ames Laboratory provided the technical expertise and supplied experimental materials needed to assess the technology of high energy bonded permanent magnets that are injection or compression molded for use in the Advanced Electric Traction System motor. This support was a sustained (Phase 1: 6/07 to 3/08) engineering effort that builds on the research achievements of the primary FreedomCAR project at Ames Laboratory on development of high temperature magnet alloy particulate in both flake and spherical powder forms. Ames Lab also provide guidance and direction in selection of magnet materials and supported the fabrication of experimental magnet materials for development of injection molding and magnetization processes by Arnold Magnetics, another project partner. The work with Arnold Magnetics involved a close collaboration on particulate material design and processing to achieve enhanced particulate properties and magnetic performance in the resulting bonded magnets. The overall project direction was provided by GM Program Management and two design reviews were held at GM-ATC in Torrance, CA. Ames Lab utilized current expertise in magnet powder alloy design and processing, along with on-going research advances being achieved under the existing FreedomCAR Program project to help guide and direct work during Phase 1 for the Advanced Electric Traction System Technology Development Program. The technical tasks included review of previous GM and Arnold Magnets work and identification of improvements to the benchmark magnet material, Magnequench MQP-14-12. Other benchmark characteristics of the desired magnet material include 64% volumetric loading with PPS polymer and a recommended maximum use temperature of 200C. A collaborative relationship was maintained with Arnold Magnets on the specification and processing of the bonded magnet material required by GM-ATC.

  4. Advanced neutron absorber materials

    DOEpatents

    Branagan, Daniel J.; Smolik, Galen R.

    2000-01-01

    A neutron absorbing material and method utilizing rare earth elements such as gadolinium, europium and samarium to form metallic glasses and/or noble base nano/microcrystalline materials, the neutron absorbing material having a combination of superior neutron capture cross sections coupled with enhanced resistance to corrosion, oxidation and leaching.

  5. Advanced Materials Technology

    NASA Technical Reports Server (NTRS)

    Blankenship, C. P. (Compiler); Teichman, L. A. (Compiler)

    1982-01-01

    Composites, polymer science, metallic materials (aluminum, titanium, and superalloys), materials processing technology, materials durability in the aerospace environment, ceramics, fatigue and fracture mechanics, tribology, and nondestructive evaluation (NDE) are discussed. Research and development activities are introduced to the nonaerospace industry. In order to provide a convenient means to help transfer aerospace technology to the commercial mainstream in a systematic manner.

  6. Advanced materials nanocharacterization

    NASA Astrophysics Data System (ADS)

    Giannazzo, Filippo; Eyben, Pierre; Baranowski, Jacek; Camassel, Jean; Lányi, Stefan

    2011-12-01

    This special issue of Nanoscale Research Letters contains scientific contributions presented at the Symposium D "Multidimensional Electrical and Chemical Characterization at the Nanometer-scale of Organic and Inorganic Semiconductors" of the E-MRS Fall Meeting 2010, which was held in Warsaw, Poland from 13th to 17th September, 2010.

  7. Development of advanced thermoelectric materials

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The development of an advanced thermoelectric material for radioisotope thermoelectric generator (RTG) applications is reported. A number of materials were explored. The bulk of the effort, however, was devoted to improving silicon germanium alloys by the addition of gallium phosphide, the synthesis and evaluation of lanthanum chrome sulfide and the formulation of various mixtures of lanthanum sulfide and chrome sulfide. It is found that each of these materials exhibits promise as a thermoelectric material.

  8. Advanced Pressure Boundary Materials

    SciTech Connect

    Santella, Michael L; Shingledecker, John P

    2007-01-01

    Increasing the operating temperatures of fossil power plants is fundamental to improving thermal efficiencies and reducing undesirable emissions such as CO{sub 2}. One group of alloys with the potential to satisfy the conditions required of higher operating temperatures is the advanced ferritic steels such as ASTM Grade 91, 9Cr-2W, and 12Cr-2W. These are Cr-Mo steels containing 9-12 wt% Cr that have martensitic microstructures. Research aimed at increasing the operating temperature limits of the 9-12 wt% Cr steels and optimizing them for specific power plant applications has been actively pursued since the 1970's. As with all of the high strength martensitic steels, specifying upper temperature limits for tempering the alloys and heat treating weldments is a critical issue. To support this aspect of development, thermodynamic analysis was used to estimate how this critical temperature, the A{sub 1} in steel terminology, varies with alloy composition. The results from the thermodynamic analysis were presented to the Strength of Weldments subgroup of the ASME Boiler & Pressure Vessel Code and are being considered in establishing maximum postweld heat treatment temperatures. Experiments are also being planned to verify predictions. This is part of a CRADA project being done with Alstom Power, Inc.

  9. Advanced materials for space

    NASA Technical Reports Server (NTRS)

    Tenney, D. R.; Slemp, W. S.; Long, E. R., Jr.; Sykes, G. F.

    1980-01-01

    The principal thrust of the LSST program is to develop the materials technology required for confident design of large space systems such as antennas and platforms. Areas of research in the FY-79 program include evaluation of polysulfones, measurement of the coefficient of thermal expansion of low expansion composite laminates, thermal cycling effects, and cable technology. The development of new long thermal control coatings and adhesives for use in space is discussed. The determination of radiation damage mechanisms of resin matrix composites and the formulation of new polymer matrices that are inherently more stable in the space environment are examined.

  10. Fatigue of advanced materials

    SciTech Connect

    Dauskardt, R.H.; Ritchie, R.O. . Center for Advanced Materials); Cox, B.N. )

    1993-08-01

    The development of toughened ceramics over the past 10 to 15 years is arguably one of the most important materials breakthroughs of this century. Monolithic and composite ceramic materials having fracture toughnesses up to an order of magnitude higher than those available 20 years ago have been produced using technologies based on scientific understanding and micromechanical models for in situ phase transformation, fiber bridging, ductile-particle toughening, and other toughening mechanisms. The irony of this, however, is that although ceramics can now be seriously considered for many structural applications, they can also, contrary to popular belief, be susceptible to degradation under cyclic fatigue loading. This is true even when the loading is fully compressive. As a result, a great deal of attention is now being paid to ceramic fatigue, largely because of the importance of cyclic loading in many of the potential applications for ceramics, such as gas-turbine and reciprocating engines. However, because the field is in its infancy, only limited fatigue property data have been documented, understanding of salient fatigue mechanisms has not been achieved, and the design of ceramic microstructures for optimum fatigue resistance has yet to be attempted.

  11. Overview on NASA's Advanced Electric Propulsion Concepts Activities

    NASA Technical Reports Server (NTRS)

    Frisbee, Robert H.

    1999-01-01

    Advanced electric propulsion research activities are currently underway that seek to addresses feasibility issues of a wide range of advanced concepts, and may result in the development of technologies that will enable exciting new missions within our solar system and beyond. Each research activity is described in terms of the present focus and potential future applications. Topics include micro-electric thrusters, electrodynamic tethers, high power plasma thrusters and related applications in materials processing, variable specific impulse plasma thrusters, pulsed inductive thrusters, computational techniques for thruster modeling, and advanced electric propulsion missions and systems studies.

  12. Advanced Aerospace Materials by Design

    NASA Technical Reports Server (NTRS)

    Srivastava, Deepak; Djomehri, Jahed; Wei, Chen-Yu

    2004-01-01

    The advances in the emerging field of nanophase thermal and structural composite materials; materials with embedded sensors and actuators for morphing structures; light-weight composite materials for energy and power storage; and large surface area materials for in-situ resource generation and waste recycling, are expected to :revolutionize the capabilities of virtually every system comprising of future robotic and :human moon and mars exploration missions. A high-performance multiscale simulation platform, including the computational capabilities and resources of Columbia - the new supercomputer, is being developed to discover, validate, and prototype next generation (of such advanced materials. This exhibit will describe the porting and scaling of multiscale 'physics based core computer simulation codes for discovering and designing carbon nanotube-polymer composite materials for light-weight load bearing structural and 'thermal protection applications.

  13. Future requirements for advanced materials

    NASA Technical Reports Server (NTRS)

    Olstad, W. B.

    1980-01-01

    Recent advances and future trends in aerospace materials technology are reviewed with reference to metal alloys, high-temperature composites and adhesives, tungsten fiber-reinforced superalloys, hybrid materials, ceramics, new ablative materials, such as carbon-carbon composite and silica tiles used in the Shuttle Orbiter. The technologies of powder metallurgy coupled with hot isostatic pressing, near net forging, complex large shape casting, chopped fiber molding, superplastic forming, and computer-aided design and manufacture are emphasized.

  14. FTIR characterization of advanced materials

    NASA Technical Reports Server (NTRS)

    Young, P. R.; Chang, A. C.

    1986-01-01

    This paper surveys the application of Fourier transform infrared spectroscopy to the characterization of advanced materials. FTIR sampling techniques including internal and external reflectance and photoacoustic spectroscopy are discussed. Representative examples from the literature of the analysis of resins, fibers, prepregs and composites are reviewed. A discussion of several promising specialized FTIR techniques is also presented.

  15. Hybrid and Electric Advanced Vehicle Systems Simulation

    NASA Technical Reports Server (NTRS)

    Beach, R. F.; Hammond, R. A.; Mcgehee, R. K.

    1985-01-01

    Predefined components connected to represent wide variety of propulsion systems. Hybrid and Electric Advanced Vehicle System (HEAVY) computer program is flexible tool for evaluating performance and cost of electric and hybrid vehicle propulsion systems. Allows designer to quickly, conveniently, and economically predict performance of proposed drive train.

  16. Characterization of advanced electric propulsion systems

    NASA Technical Reports Server (NTRS)

    Ray, P. K.

    1982-01-01

    Characteristic parameters of several advanced electric propulsion systems are evaluated and compared. The propulsion systems studied are mass driver, rail gun, argon MPD thruster, hydrogen free radical thruster and mercury electron bombardment ion engine. Overall, ion engines have somewhat better characteristics as compared to the other electric propulsion systems.

  17. Characterization of advanced electronic materials

    SciTech Connect

    Arko, A.J.; Heffner, R.H.; Hundley, M.F.

    1997-08-01

    This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Our goal has been to extend the Laboratory`s competency in nuclear and advanced materials by characterizing (measuring and interpreting) physical properties of advanced electronic materials and in this process to bridge the gap between materials synthesis and theoretical understanding. Attention has focused on discovering new physics by understanding the ground states of materials in which electronic correlations dominate their properties. Among several accomplishments, we have discovered and interpreted pressure-induced superconductivity in CeRh{sub 2}Si{sub 2}, boron content in UBe{sub 13-x}B{sub x} and the origin of small gaps in the spin and charge excitation spectra of Ce{sub 3}Bi{sub 4}Pt{sub 3}, and we provided seminal understanding of large magnetoresistive effects in La{sub 1-x}Ca{sub x}MnO{sub 3}. This work has established new research directions at LANL and elsewhere, involved numerous collaborators from throughout the world and attracted several postdoctoral fellows.

  18. Plasma Processing of Advanced Materials

    SciTech Connect

    Heberlein, Joachim, V.R.; Pfender, Emil; Kortshagen, Uwe

    2005-02-28

    Plasma Processing of Advanced Materials The project had the overall objective of improving our understanding of the influences of process parameters on the properties of advanced superhard materials. The focus was on high rate deposition processes using thermal plasmas and atmospheric pressure glow discharges, and the emphasis on superhard materials was chosen because of the potential impact of such materials on industrial energy use and on the environment. In addition, the development of suitable diagnostic techniques was pursued. The project was divided into four tasks: (1) Deposition of superhard boron containing films using a supersonic plasma jet reactor (SPJR), and the characterization of the deposition process. (2) Deposition of superhard nanocomposite films in the silicon-nitrogen-carbon system using the triple torch plasma reactor (TTPR), and the characterization of the deposition process. (3) Deposition of films consisting of carbon nanotubes using an atmospheric pressure glow discharge reactor. (4) Adapting the Thomson scattering method for characterization of atmospheric pressure non-uniform plasmas with steep spatial gradients and temporal fluctuations. This report summarizes the results.

  19. Advanced aircraft engine materials trends

    NASA Technical Reports Server (NTRS)

    Dreshfield, R. L.; Gray, H. R.; Levine, S. R.; Signorelli, R.

    1981-01-01

    Recent activities of the Lewis Research Center are reviewed which are directed toward developing materials for rotating hot section components for aircraft gas turbines. Turbine blade materials activities are directed at increasing metal temperatures approximately 100 C compared to current directionally solidified alloys by use of oxide dispersion strengthening or tungsten alloy wire reinforcement of nickel or iron base superalloys. The application of thermal barrier coatings offers a promise of increasing gas temperatures an additional 100 C with current cooling technology. For turbine disk alloys, activities are directed toward reducing the cost of turbine disks by 50 percent through near net shape fabrication of prealloyed powders as well as towards improved performance. In addition, advanced alloy concepts and fabrication methods for dual alloy disks are being studied as having potential for improving the life of future high performance disks and reducing the amount of strategic materials required in these components.

  20. Materials Challenges for Advanced Combustion and Gasification Fossil Energy Systems

    NASA Astrophysics Data System (ADS)

    Sridhar, S.; Rozzelle, P.; Morreale, B.; Alman, D.

    2011-04-01

    This special section of Metallurgical and Materials Transactions is devoted to materials challenges associated with coal based energy conversion systems. The purpose of this introductory article is to provide a brief outline to the challenges associated with advanced combustion and advanced gasification, which has the potential of providing clean, affordable electricity by improving process efficiency and implementing carbon capture and sequestration. Affordable materials that can meet the demanding performance requirements will be a key enabling technology for these systems.

  1. Material Challenges and Opportunities for Commercial Electric Aircraft

    NASA Technical Reports Server (NTRS)

    Misra, Ajay

    2014-01-01

    Significant reduction in carbon dioxide emission for future air transportation system will require adoption of electric propulsion system and more electric architectures. Various options for aircraft electric propulsion include hybrid electric, turboelectric, and full electric system. Realization of electric propulsion system for commercial aircraft applications will require significant increases in power density of electric motors and energy density of energy storage system, such as the batteries and fuel cells. In addition, transmission of MW of power in the aircraft will require high voltage power transmission system to reduce the weight of the power transmission system. Finally, there will be significant thermal management challenges. Significant advances in material technologies will be required to meet these challenges. Technologies of interest include materials with higher electrical conductivity than Cu, high thermal conductivity materials, and lightweight electrically insulating materials with high breakdown voltage, high temperature magnets, advanced battery and fuel cell materials, and multifunctional materials. The presentation will include various challenges for commercial electric aircraft and provide an overview of material improvements that will be required to meet these challenges.

  2. Advanced High Efficiency Thermoelectric Materials

    NASA Astrophysics Data System (ADS)

    Flanders, Laffite; Cummer, Keith R.; Feinsinger, Joseph; Heshmatpour, Ben

    2006-01-01

    The research effort at Teledyne Energy Systems, Inc., which has been aimed at improving the performance of the currently used thermoelectric (TE) materials has identified a number of improved formulations for the standard n-type PbTe and p-type TAGS. The preliminary test results appear to indicate nearly 50% higher thermal to electric energy conversion efficiency for these new PbTe and TAGS formulations. Effort is continuing to confirm the preliminary test results and validate the materials fabrication processes. Multiple batches of the newly developed TE materials will be prepared and characterized for thermoelectric properties. The selected TE materials will be subjected to degradation analysis and life modeling to determine any deterioration in the TE properties as a function of time and operating temperatures. This effort also includes measurement of sublimation rates as a function of temperature for the selected materials. The results for the initial sublimation tests are quite encouraging and show appreciable reduction in sublimation rate for TAGS 80 and the modified TAGS alloys. Future effort will include determination of effect of sublimation on TE characteristics for the selected TE materials. Microanalysis technique such as optical and electron microscopy, XRD and EDSX will be used to determine the microstructural characteristics of the TE materials at various stages of their simulated operating life. Based on the results of these studies the n-type and p-type materials with the highest power conversion efficiency and the lowest degradation rate will be selected for use in fabrication of future thermoelectric devices.

  3. Session: CSP Advanced Systems: Optical Materials (Presentation)

    SciTech Connect

    Kennedy, C.

    2008-04-01

    The Optical Materials project description is to characterize advanced reflector, perform accelerated and outdoor testing of commercial and experimental reflector materials, and provide industry support.

  4. Advanced materials for space applications

    NASA Astrophysics Data System (ADS)

    Pater, Ruth H.; Curto, Paul A.

    2007-12-01

    Since NASA was created in 1958, over 6400 patents have been issued to the agency—nearly one in a thousand of all patents ever issued in the United States. A large number of these inventions have focused on new materials that have made space travel and exploration of the moon, Mars, and the outer planets possible. In the last few years, the materials developed by NASA Langley Research Center embody breakthroughs in performance and properties that will enable great achievements in space. The examples discussed below offer significant advantages for use in small satellites, i.e., those with payloads under a metric ton. These include patented products such as LaRC SI, LaRC RP 46, LaRC RP 50, PETI-5, TEEK, PETI-330, LaRC CP, TOR-LM and LaRC LCR (patent pending). These and other new advances in nanotechnology engineering, self-assembling nanostructures and multifunctional aerospace materials are presented and discussed below, and applications with significant technological and commercial advantages are proposed.

  5. Advanced Materials for Space Applications

    NASA Technical Reports Server (NTRS)

    Pater, Ruth H.; Curto, Paul A.

    2005-01-01

    Since NASA was created in 1958, over 6400 patents have been issued to the agency--nearly one in a thousand of all patents ever issued in the United States. A large number of these inventions have focused on new materials that have made space travel and exploration of the moon, Mars, and the outer planets possible. In the last few years, the materials developed by NASA Langley Research Center embody breakthroughs in performance and properties that will enable great achievements in space. The examples discussed below offer significant advantages for use in small satellites, i.e., those with payloads under a metric ton. These include patented products such as LaRC SI, LaRC RP 46, LaRC RP 50, PETI-5, TEEK, PETI-330, LaRC CP, TOR-LM and LaRC LCR (patent pending). These and other new advances in nanotechnology engineering, self-assembling nanostructures and multifunctional aerospace materials are presented and discussed below, and applications with significant technological and commercial advantages are proposed.

  6. Materials Advance Chemical Propulsion Technology

    NASA Technical Reports Server (NTRS)

    2012-01-01

    In the future, the Planetary Science Division of NASA's Science Mission Directorate hopes to use better-performing and lower-cost propulsion systems to send rovers, probes, and observers to places like Mars, Jupiter, and Saturn. For such purposes, a new propulsion technology called the Advanced Materials Bipropellant Rocket (AMBR) was developed under NASA's In-Space Propulsion Technology (ISPT) project, located at Glenn Research Center. As an advanced chemical propulsion system, AMBR uses nitrogen tetroxide oxidizer and hydrazine fuel to propel a spacecraft. Based on current research and development efforts, the technology shows great promise for increasing engine operation and engine lifespan, as well as lowering manufacturing costs. In developing AMBR, ISPT has several goals: to decrease the time it takes for a spacecraft to travel to its destination, reduce the cost of making the propulsion system, and lessen the weight of the propulsion system. If goals like these are met, it could result in greater capabilities for in-space science investigations. For example, if the amount (and weight) of propellant required on a spacecraft is reduced, more scientific instruments (and weight) could be added to the spacecraft. To achieve AMBR s maximum potential performance, the engine needed to be capable of operating at extremely high temperatures and pressure. To this end, ISPT required engine chambers made of iridium-coated rhenium (strong, high-temperature metallic elements) that allowed operation at temperatures close to 4,000 F. In addition, ISPT needed an advanced manufacturing technique for better coating methods to increase the strength of the engine chamber without increasing the costs of fabricating the chamber.

  7. Advances in functional electrical stimulation (FES).

    PubMed

    Popović, Dejan B

    2014-12-01

    This review discusses the advancements that are needed to enhance the effects of electrical stimulation for restoring or assisting movement in humans with an injury/disease of the central nervous system. A complex model of the effects of electrical stimulation of peripheral systems is presented. The model indicates that both the motor and sensory systems are activated by electrical stimulation. We propose that a hierarchical hybrid controller may be suitable for functional electrical stimulation (FES) because this type of controller acts as a structural mimetic of its biological counterpart. Specific attention is given to the neural systems at the periphery with respect to the required electrodes and stimulators. Furthermore, we note that FES with surface electrodes is preferred for the therapy, although there is a definite advantage associated with implantable technology for life-long use. The last section of the review discusses the potential need to combine FES and robotic systems to provide assistance in some cases. PMID:25287528

  8. The recycling dilemma for advanced materials use: Automobile materials substitution

    SciTech Connect

    Field, F.R. III; Clark, J.P. )

    1991-01-01

    This paper discusses the difficulties associated with imposing recycling imperatives upon advanced materials development by examining the case of automotive materials substitution and its impacts upon the recyclability of the automobile. Parallels are drawn between today's issues, which focus upon the recyclability of the increasing polymeric fraction in automobile shredder fluff, and the junked automobile problem of the 1960's, when the problem of abandoned automobiles became a part of the environmental and legislative agenda in the US and overseas. In the 1960's, both the source and the resolution of the junk automobile problem arose through a confluence of technological and economic factors, rather than through any set of regulatory influences. The rise of electric arc furnace steelmaking and the development of the automobile shredder were sufficient to virtually eliminate the problem - so much so that today's problems are incorrectly viewed as novelties. Today's automobile recycling problem again derives from technological and economic factors, but regulatory influences have spurred some of them. While there are no lack of technological solutions to the problem of automobile shredder fluff, none of these solutions yet provides scrap processors with the kind of profit opportunity necessary to implement them. In some ways, it is implicit in advanced materials markets that there is little to no demand for recycled forms of these materials, and, in the absence of these markets, there are few reasons to expect that the solution to today's problems will be quite so neat.

  9. Advanced Ceramic Interconnect Material for Solid Oxide Fuel Cells: Electrical and Thermal Properties of Calcium- and Nickel-Doped Yttrium Chromites

    SciTech Connect

    Yoon, Kyung J.; Cramer, Carolyn N.; Stevenson, Jeffry W.; Marina, Olga A.

    2010-11-15

    The structural, thermal and electrical characteristics of calcium- and nickel-doped yttrium chromites were studied for potential use as the interconnect material in high temperature solid oxide fuel cells (SOFCs) and other high temperature electrochemical and thermoelectric devices. The Y0.8Ca0.2Cr1-xNixO3±δ compositions with x=0-0.15 showed single phase orthorhombic perovskite structures between 25 and 1200 degrees C over a wide range of oxygen partial pressures. Nickel doping remarkably enhanced sintering behavior of otherwise refractory chromites, and densities 94% of theoretical density were obtained after sintering at 1400 degrees C in air with 15 at.% Ni. The thermal expansion coefficient (TEC) was increased with nickel content to closely match that of an 8 mol% yttria-stabilized zirconia (YSZ) electrolyte for 0.05 ≤ x ≤ 0.15. Nickel doping significantly improved the electrical conductivity in both oxidizing and reducing atmospheres. Undesirable oxygen ion leakage current was insignificant in dual atmosphere conditions. No interfacial interactions with YSZ were detected after firing at 1400 degrees C.

  10. Advanced materials: Information and analysis needs

    SciTech Connect

    Curlee, T.R.; Das, S.; Lee, R.; Trumble, D.

    1990-09-01

    This report presents the findings of a study to identify the types of information and analysis that are needed for advanced materials. The project was sponsored by the US Bureau of Mines (BOM). It includes a conceptual description of information needs for advanced materials and the development and implementation of a questionnaire on the same subject. This report identifies twelve fundamental differences between advanced and traditional materials and discusses the implications of these differences for data and analysis needs. Advanced and traditional materials differ significantly in terms of physical and chemical properties. Advanced material properties can be customized more easily. The production of advanced materials may differ from traditional materials in terms of inputs, the importance of by-products, the importance of different processing steps (especially fabrication), and scale economies. The potential for change in advanced materials characteristics and markets is greater and is derived from the marriage of radically different materials and processes. In addition to the conceptual study, a questionnaire was developed and implemented to assess the opinions of people who are likely users of BOM information on advanced materials. The results of the questionnaire, which was sent to about 1000 people, generally confirm the propositions set forth in the conceptual part of the study. The results also provide data on the categories of advanced materials and the types of information that are of greatest interest to potential users. 32 refs., 1 fig., 12 tabs.

  11. Recycling of Advanced Batteries for Electric Vehicles

    SciTech Connect

    JUNGST,RUDOLPH G.

    1999-10-06

    The pace of development and fielding of electric vehicles is briefly described and the principal advanced battery chemistries expected to be used in the EV application are identified as Ni/MH in the near term and Li-ion/Li-polymer in the intermediate to long term. The status of recycling process development is reviewed for each of the two chemistries and future research needs are discussed.

  12. New Advance in SuperConducting Materials

    ScienceCinema

    None

    2010-01-08

    Superconducting materials will transform the world's electrical infrastructure, saving billions of dollars once the technical details and installation are in place. At Los Alamos National Laborator...  

  13. New Advance in SuperConducting Materials

    SciTech Connect

    2009-03-02

    Superconducting materials will transform the world's electrical infrastructure, saving billions of dollars once the technical details and installation are in place. At Los Alamos National Laborator...  

  14. Advanced Reflector and Absorber Materials (Fact Sheet)

    SciTech Connect

    Not Available

    2010-08-01

    Fact sheet describing NREL CSP Program capabilities in the area of advanced reflector and absorber materials: evaluating performance, determining degradation rates and lifetime, and developing new coatings.

  15. New Advances in SuperConducting Materials

    ScienceCinema

    None

    2014-08-12

    Superconducting materials will transform the world's electrical infrastructure, saving billions of dollars once the technical details and installation are in place. At Los Alamos National Laboratory, new materials science concepts are bringing this essential technology closer to widespread industrial use.

  16. Materials for advanced ultrasupercritical steam turbines

    SciTech Connect

    Purgert, Robert; Shingledecker, John; Saha, Deepak; Thangirala, Mani; Booras, George; Powers, John; Riley, Colin; Hendrix, Howard

    2015-12-01

    The U.S. Department of Energy (DOE) and the Ohio Coal Development Office (OCDO) have sponsored a project aimed at identifying, evaluating, and qualifying the materials needed for the construction of the critical components of coal-fired power plants capable of operating at much higher efficiencies than the current generation of supercritical plants. This increased efficiency is expected to be achieved principally through the use of advanced ultrasupercritical (A-USC) steam conditions. A limiting factor in this can be the materials of construction for boilers and for steam turbines. The overall project goal is to assess/develop materials technology that will enable achieving turbine throttle steam conditions of 760°C (1400°F)/35MPa (5000 psi). This final technical report covers the research completed by the General Electric Company (GE) and Electric Power Research Institute (EPRI), with support from Oak Ridge National Laboratory (ORNL) and the National Energy Technology Laboratory (NETL) – Albany Research Center, to develop the A-USC steam turbine materials technology to meet the overall project goals. Specifically, this report summarizes the industrial scale-up and materials property database development for non-welded rotors (disc forgings), buckets (blades), bolting, castings (needed for casing and valve bodies), casting weld repair, and casting to pipe welding. Additionally, the report provides an engineering and economic assessment of an A-USC power plant without and with partial carbon capture and storage. This research project successfully demonstrated the materials technology at a sufficient scale and with corresponding materials property data to enable the design of an A-USC steam turbine. The key accomplishments included the development of a triple-melt and forged Haynes 282 disc for bolted rotor construction, long-term property development for Nimonic 105 for blading and bolting, successful scale-up of Haynes 282 and Nimonic 263 castings using

  17. Advanced Photon Source Upgrade Project - Materials

    ScienceCinema

    Gibbson, Murray;

    2013-04-19

    An upgrade to Advanced Photon Source announced by DOE - http://go.usa.gov/ivZ -- will help scientists break through bottlenecks in materials design in order to develop materials with desirable functions.

  18. Advanced Photon Source Upgrade Project - Materials

    SciTech Connect

    Gibbson, Murray

    2011-01-01

    An upgrade to Advanced Photon Source announced by DOE - http://go.usa.gov/ivZ -- will help scientists break through bottlenecks in materials design in order to develop materials with desirable functions.

  19. Application of advanced materials to rotating machines

    NASA Technical Reports Server (NTRS)

    Triner, J. E.

    1983-01-01

    In discussing the application of advanced materials to rotating machinery, the following topics are covered: the torque speed characteristics of ac and dc machines, motor and transformer losses, the factors affecting core loss in motors, advanced magnetic materials and conductors, and design tradeoffs for samarium cobalt motors.

  20. Video Fact Sheets: Everyday Advanced Materials

    SciTech Connect

    2015-10-06

    What are Advanced Materials? Ames Laboratory is behind some of the best advanced materials out there. Some of those include: Lead-Free Solder, Photonic Band-Gap Crystals, Terfenol-D, Aluminum-Calcium Power Cable and Nano Particles. Some of these are in products we use every day.

  1. Development of Specialized Advanced Materials Curriculum.

    ERIC Educational Resources Information Center

    Malmgren, Thomas; And Others

    This course is intended to give students a comprehensive experience in current and future manufacturing materials and processes. It familiarizes students with: (1) base of composite materials; (2) composites--a very light, strong material used in spacecraft and stealth aircraft; (3) laminates; (4) advanced materials--especially aluminum alloys;…

  2. New raw material for electrical porcelain

    SciTech Connect

    Khristoforov, K.K.; Portnova, I.G.; Omel'chenko, Yu.A.

    1986-09-01

    Research is described in finding new raw materials for the fabrication of porcelain electrical insulators for power transmission lines. The materials tested come from several deposits in the Soviet Union and include alumina minerals, quartz, feldspars, pegmatites, clays, and two kaolins, as well as waste materials recovered from porcelain production. Comparative electrical and mechanical properties, grain sizes, sinterabilities, and mineral compositions are tabulated for the candidate materials.

  3. Advanced Materials and Processing 2010

    NASA Astrophysics Data System (ADS)

    Zhang, Yunfeng; Su, Chun Wei; Xia, Hui; Xiao, Pengfei

    2011-06-01

    Strain sensors made from MWNT/polymer nanocomposites / Gang Yin, Ning Hu and Yuan Li -- Shear band evolution and nanostructure formation in titanium by cold rolling / Dengke Yang, Peter D. Hodgson and Cuie Wen -- Biodegradable Mg-Zr-Ca alloys for bone implant materials / Yuncang Li ... [et al.] -- Hydroxyapatite synthesized from nanosized calcium carbonate via hydrothermal method / Yu-Shiang Wu, Wen-Ku Chang and Min Jou -- Modeling of the magnetization process and orthogonal fluxgate sensitivity of ferromagnetic micro-wire arrays / Fan Jie ... [et al.] -- Fabrication of silicon oxide nanowires on Ni coated silicon substrate by simple heating process / Bo Peng and Kwon-Koo Cho -- Deposition of TiOxNy thin films with various nitrogen flow rate: growth behavior and structural properties / S.-J. Cho ... [et al.] -- Observation on photoluminescence evolution in 300 KeV self-ion implanted and annealed silicon / Yu Yang ... [et al.] -- Facile synthesis of lithium niobate from a novel precursor H[symbol] / Meinan Liu ... [et al.] -- Effects of the buffer layers on the adhesion and antimicrobial properties of the amorphous ZrAlNiCuSi films / Pai-Tsung Chiang ... [et al.] -- Fabrication of ZnO nanorods by electrochemical deposition process and its photovoltaic properties / Jin-Hwa Kim ... [et al.] -- Cryogenic resistivities of NbTiAlVTaLax, CoCrFeNiCu and CoCrFeNiAl high entropy alloys / Xiao Yang and Yong Zhang -- Modeling of centrifugal force field and the effect on filling and solidification in centrifugal casting / Wenbin Sheng, Chunxue Ma and Wanli Gu -- Electrochemical properties of TiO[symbol] nanotube arrays film prepared by anodic oxidation / Young-Jin Choi ... [et al.] -- Effect of Ce additions on high temperature properties of Mg-5Sn-3Al-1Zn alloy / Byoung Soo Kang ... [et al.] -- Sono-electroless plating of Ni-Mo-P film / Atsushi Chiba, Masato Kanou and Wen-Chang Wu -- Diameter dependence of giant magneto-impedance effect in co-based melt extracted amorphous

  4. Recent Advances in Superhard Materials

    NASA Astrophysics Data System (ADS)

    Zhao, Zhisheng; Xu, Bo; Tian, Yongjun

    2016-07-01

    In superhard materials research, two topics are of central focus. One is to understand hardness microscopically and to establish hardness models with atomic parameters, which can be used to guide the design or prediction of novel superhard crystals. The other is to synthesize superhard materials with enhanced comprehensive performance (i.e., hardness, fracture toughness, and thermal stability), with the ambition of achieving materials harder than natural diamond. In this review, we present recent developments in both areas. The microscopic hardness models of covalent single crystals are introduced and further generalized to polycrystalline materials. Current research progress in novel superhard materials and nanostructuring approaches for high-performance superhard materials are discussed. We also clarify a long-standing controversy about the criterion for performing a reliable indentation hardness measurement.

  5. Synthesis of Advanced Energetic Materials

    NASA Astrophysics Data System (ADS)

    Wilson, Rebecca

    2015-06-01

    For a given energetic material, performance is a combination of the rate of energy release and total energy content. Organic and metal-based energetics, respectively, represent the limiting cases, exhibiting strength in one area and weakness in the other. Many organic energetic materials readily detonate, but increasing total energy content using only known energetic functional groups is difficult. In contrast, combustion of aluminum metal can release more than three times the energy available from the same mass of organic explosive, but the rate of energy release is slow relative to detonation, and combustion is often incomplete. Current research in our department seeks to improve both the total energy content of organic explosives and the rate of combustion of aluminum-based materials. Novel arrangements of atoms within energetic molecules, along with new assembly methods for materials, are employed to improve both aspects of performance. In the case of organic energetic materials, novel functional groups can yield compounds with higher density, and therefore greater power, relative to conventional, nitro group-based materials. For aluminum-based materials, progressively smaller particles undergo more rapid and complete combustion. To prevent surface oxidation, one approach is to shield a core of low-valent aluminum atoms with a shell of ligands, while another is to develop aluminum-based fuels that are inherently air-stable. These methods will be discussed in the context of novel energetic materials synthesis. Research Department, NSWC IHEODTD.

  6. Micromechanical modeling of advanced materials

    SciTech Connect

    Silling, S.A.; Taylor, P.A.; Wise, J.L.; Furnish, M.D.

    1994-04-01

    Funded as a laboratory-directed research and development (LDRD) project, the work reported here focuses on the development of a computational methodology to determine the dynamic response of heterogeneous solids on the basis of their composition and microstructural morphology. Using the solid dynamics wavecode CTH, material response is simulated on a scale sufficiently fine to explicitly represent the material`s microstructure. Conducting {open_quotes}numerical experiments{close_quotes} on this scale, the authors explore the influence that the microstructure exerts on the material`s overall response. These results are used in the development of constitutive models that take into account the effects of microstructure without explicit representation of its features. Applying this methodology to a glass-reinforced plastic (GRP) composite, the authors examined the influence of various aspects of the composite`s microstructure on its response in a loading regime typical of impact and penetration. As a prerequisite to the microscale modeling effort, they conducted extensive materials testing on the constituents, S-2 glass and epoxy resin (UF-3283), obtaining the first Hugoniot and spall data for these materials. The results of this work are used in the development of constitutive models for GRP materials in transient-dynamics computer wavecodes.

  7. Advanced Materials for Automotive Application

    NASA Astrophysics Data System (ADS)

    Tisza, M.

    2013-12-01

    In this paper some recent material developments will be overviewed mainly from the point of view of automotive industry. In car industry, metal forming is one of the most important manufacturing processes imposing severe restrictions on materials; these are often contradictory requirements, e.g. high strength simultaneously with good formability, etc. Due to these challenges and the ever increasing demand new material classes have been developed; however, the more and more wide application of high strength materials meeting the requirements stated by the mass reduction lead to increasing difficulties concerning the formability which requires significant technological developments as well. In this paper, the recent materials developments will be overviewed from the point of view of the automotive industry.

  8. Shock-loading response of advanced materials

    NASA Astrophysics Data System (ADS)

    Gray, G. T., III

    1993-05-01

    Advanced materials, such as composites (metal, ceramic, or polymer-matrix), intermetallics, foams (metallic or polymeric-based), laminated materials, and nanostructured materials are receiving increasing attention because their properties can be custom tailored specific applications. The high-rate/impact response of advanced materials is relevant to a broad range of service environments such as the crashworthiness of civilian/military vehicles, foreign-object-damage in aerospace, and light-weight armor. Increased utilization of these material classes under dynamic loading conditions requires an understanding of the relationship between high-rate/shock-wave response as a function of microstructure if we are to develop models to predict material behavior. In this paper, the issues relevant to defect generation, storage, and the underlying physical basis needed in predictive models for several advanced materials are reviewed.

  9. Development of advanced thermoelectric materials, phase A

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Work performed on the chemical system characterized by chrome sulfide, chrome selenide, lanthanum selenide, and lanthanum sulfide is described. Most materials within the chemical systems possess the requisites for attractive thermoelectric materials. The preparation of the alloys is discussed. Graphs show the Seebeck coefficient, electrical resistivity, and thermal conductivity of various materials within the chemical systems. The results of selected doping are included.

  10. Nuclear material investigations by advanced analytical techniques

    NASA Astrophysics Data System (ADS)

    Degueldre, C.; Kuri, G.; Martin, M.; Froideval, A.; Cammelli, S.; Orlov, A.; Bertsch, J.; Pouchon, M. A.

    2010-10-01

    Advanced analytical techniques have been used to characterize nuclear materials at the Paul Scherrer Institute during the last decade. The analysed materials ranged from reactor pressure vessel (RPV) steels, Zircaloy claddings to fuel samples. The processes studied included copper cluster build up in RPV steels, corrosion, mechanical and irradiation damage behaviour of PWR and BWR cladding materials as well as fuel defect development. The used advanced techniques included muon spin resonance spectroscopy for zirconium alloy defect characterization while fuel element materials were analysed by techniques derived from neutron and X-ray scattering and absorption spectroscopy.

  11. Characterization of advanced electric propulsion systems

    NASA Technical Reports Server (NTRS)

    Ray, P. K.

    1982-01-01

    Characteristics of several advanced electric propulsion systems are evaluated and compared. The propulsion systems studied are mass driver, rail gun, MPD thruster, hydrogen free radical thruster and mercury electron bombardment ion engine. These are characterized by specific impulse, overall efficiency, input power, average thrust, power to average thrust ratio and average thrust to dry weight ratio. Several important physical characteristics such as dry system mass, accelerator length, bore size and current pulse requirement are also evaluated in appropriate cases. Only the ion engine can operate at a specific impulse beyond 2000 sec. Rail gun, MPD thruster and free radical thruster are currently characterized by low efficiencies. Mass drivers have the best performance characteristics in terms of overall efficiency, power to average thrust ratio and average thrust to dry weight ratio. But, they can only operate at low specific impulses due to large power requirements and are extremely long due to limitations of driving current. Mercury ion engines have the next best performance characteristics while operating at higher specific impulses. It is concluded that, overall, ion engines have somewhat better characteristics as compared to the other electric propulsion systems.

  12. Ion beam processing of advanced electronic materials

    SciTech Connect

    Cheung, N.W.; Marwick, A.D.; Roberto, J.B.; International Business Machines Corp., Yorktown Heights, NY . Thomas J. Watson Research Center; Oak Ridge National Lab., TN )

    1989-01-01

    This report contains research programs discussed at the materials research society symposia on ion beam processing of advanced electronic materials. Major topics include: shallow implantation and solid-phase epitaxy; damage effects; focused ion beams; MeV implantation; high-dose implantation; implantation in III-V materials and multilayers; and implantation in electronic materials. Individual projects are processed separately for the data bases. (CBS)

  13. Advancements in electric and hybrid electric vehicle technology

    SciTech Connect

    1994-12-31

    Contents of this volume include: Influence of Battery Characteristics on Traction Drive Performance; Chassis Design for a Small Electric City Car; Thermal Comfort of Electric Vehicles; Power Quality Problems at Electric Vehicle`s Charging Station; The Development and Performance of the AMPhibian Hybrid Electric Vehicle; The Selection of Lead-Acid Batteries for Use in Hybrid Electric Vehicles; and more.

  14. Advanced Materials for Exploration Task Research Results

    NASA Technical Reports Server (NTRS)

    Cook, M. B. (Compiler); Murphy, K. L.; Schneider, T.

    2008-01-01

    The Advanced Materials for Exploration (AME) Activity in Marshall Space Flight Center s (MSFC s) Exploration Science and Technology Directorate coordinated activities from 2001 to 2006 to support in-space propulsion technologies for future missions. Working together, materials scientists and mission planners identified materials shortfalls that are limiting the performance of long-term missions. The goal of the AME project was to deliver improved materials in targeted areas to meet technology development milestones of NASA s exploration-dedicated activities. Materials research tasks were targeted in five areas: (1) Thermal management materials, (2) propulsion materials, (3) materials characterization, (4) vehicle health monitoring materials, and (5) structural materials. Selected tasks were scheduled for completion such that these new materials could be incorporated into customer development plans.

  15. Advanced Materials for Neural Surface Electrodes

    PubMed Central

    Schendel, Amelia A.; Eliceiri, Kevin W.; Williams, Justin C.

    2015-01-01

    Designing electrodes for neural interfacing applications requires deep consideration of a multitude of materials factors. These factors include, but are not limited to, the stiffness, biocompatibility, biostability, dielectric, and conductivity properties of the materials involved. The combination of materials properties chosen not only determines the ability of the device to perform its intended function, but also the extent to which the body reacts to the presence of the device after implantation. Advances in the field of materials science continue to yield new and improved materials with properties well-suited for neural applications. Although many of these materials have been well-established for non-biological applications, their use in medical devices is still relatively novel. The intention of this review is to outline new material advances for neural electrode arrays, in particular those that interface with the surface of the nervous tissue, as well as to propose future directions for neural surface electrode development. PMID:26392802

  16. Joining of advanced materials by superplastic deformation

    DOEpatents

    Goretta, Kenneth C.; Routbort, Jules L.; Gutierrez-Mora, Felipe

    2008-08-19

    A method for utilizing superplastic deformation with or without a novel joint compound that leads to the joining of advanced ceramic materials, intermetallics, and cermets. A joint formed by this approach is as strong as or stronger than the materials joined. The method does not require elaborate surface preparation or application techniques.

  17. Joining of advanced materials by superplastic deformation

    DOEpatents

    Goretta, Kenneth C.; Routbort, Jules L.; Gutierrez-Mora, Felipe

    2005-12-13

    A method for utilizing superplastic deformation with or without a novel joint compound that leads to the joining of advanced ceramic materials, intermetallics, and cermets. A joint formed by this approach is as strong as or stronger than the materials joined. The method does not require elaborate surface preparation or application techniques.

  18. Methane storage in advanced porous materials.

    PubMed

    Makal, Trevor A; Li, Jian-Rong; Lu, Weigang; Zhou, Hong-Cai

    2012-12-01

    The need for alternative fuels is greater now than ever before. With considerable sources available and low pollution factor, methane is a natural choice as petroleum replacement in cars and other mobile applications. However, efficient storage methods are still lacking to implement the application of methane in the automotive industry. Advanced porous materials, metal-organic frameworks and porous organic polymers, have received considerable attention in sorptive storage applications owing to their exceptionally high surface areas and chemically-tunable structures. In this critical review we provide an overview of the current status of the application of these two types of advanced porous materials in the storage of methane. Examples of materials exhibiting high methane storage capacities are analyzed and methods for increasing the applicability of these advanced porous materials in methane storage technologies described. PMID:22990753

  19. Advanced materials for aircraft engine applications.

    PubMed

    Backman, D G; Williams, J C

    1992-02-28

    A review of advances for aircraft engine structural materials and processes is presented. Improved materials, such as superalloys, and the processes for making turbine disks and blades have had a major impact on the capability of modern gas turbine engines. New structural materials, notably composites and intermetallic materials, are emerging that will eventually further enhance engine performance, reduce engine weight, and thereby enable new aircraft systems. In the future, successful aerospace manufacturers will combine product design and materials excellence with improved manufacturing methods to increase production efficiency, enhance product quality, and decrease the engine development cycle time. PMID:17817782

  20. Materials Requirements for Advanced Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Whitaker, Ann F.; Cook, Mary Beth; Clinton, R. G., Jr.

    2005-01-01

    NASA's mission to "reach the Moon and Mars" will be obtained only if research begins now to develop materials with expanded capabilities to reduce mass, cost and risk to the program. Current materials cannot function satisfactorily in the deep space environments and do not meet the requirements of long term space propulsion concepts for manned missions. Directed research is needed to better understand materials behavior for optimizing their processing. This research, generating a deeper understanding of material behavior, can lead to enhanced implementation of materials for future exploration vehicles. materials providing new approaches for manufacture and new options for In response to this need for more robust materials, NASA's Exploration Systems Mission Directorate (ESMD) has established a strategic research initiative dedicated to materials development supporting NASA's space propulsion needs. The Advanced Materials for Exploration (AME) element directs basic and applied research to understand material behavior and develop improved materials allowing propulsion systems to operate beyond their current limitations. This paper will discuss the approach used to direct the path of strategic research for advanced materials to ensure that the research is indeed supportive of NASA's future missions to the moon, Mars, and beyond.

  1. Advanced Materials and Processing 2010

    NASA Astrophysics Data System (ADS)

    Zhang, Yunfeng; Su, Chun Wei; Xia, Hui; Xiao, Pengfei

    2011-06-01

    Strain sensors made from MWNT/polymer nanocomposites / Gang Yin, Ning Hu and Yuan Li -- Shear band evolution and nanostructure formation in titanium by cold rolling / Dengke Yang, Peter D. Hodgson and Cuie Wen -- Biodegradable Mg-Zr-Ca alloys for bone implant materials / Yuncang Li ... [et al.] -- Hydroxyapatite synthesized from nanosized calcium carbonate via hydrothermal method / Yu-Shiang Wu, Wen-Ku Chang and Min Jou -- Modeling of the magnetization process and orthogonal fluxgate sensitivity of ferromagnetic micro-wire arrays / Fan Jie ... [et al.] -- Fabrication of silicon oxide nanowires on Ni coated silicon substrate by simple heating process / Bo Peng and Kwon-Koo Cho -- Deposition of TiOxNy thin films with various nitrogen flow rate: growth behavior and structural properties / S.-J. Cho ... [et al.] -- Observation on photoluminescence evolution in 300 KeV self-ion implanted and annealed silicon / Yu Yang ... [et al.] -- Facile synthesis of lithium niobate from a novel precursor H[symbol] / Meinan Liu ... [et al.] -- Effects of the buffer layers on the adhesion and antimicrobial properties of the amorphous ZrAlNiCuSi films / Pai-Tsung Chiang ... [et al.] -- Fabrication of ZnO nanorods by electrochemical deposition process and its photovoltaic properties / Jin-Hwa Kim ... [et al.] -- Cryogenic resistivities of NbTiAlVTaLax, CoCrFeNiCu and CoCrFeNiAl high entropy alloys / Xiao Yang and Yong Zhang -- Modeling of centrifugal force field and the effect on filling and solidification in centrifugal casting / Wenbin Sheng, Chunxue Ma and Wanli Gu -- Electrochemical properties of TiO[symbol] nanotube arrays film prepared by anodic oxidation / Young-Jin Choi ... [et al.] -- Effect of Ce additions on high temperature properties of Mg-5Sn-3Al-1Zn alloy / Byoung Soo Kang ... [et al.] -- Sono-electroless plating of Ni-Mo-P film / Atsushi Chiba, Masato Kanou and Wen-Chang Wu -- Diameter dependence of giant magneto-impedance effect in co-based melt extracted amorphous

  2. Advanced materials for geothermal energy processes

    SciTech Connect

    Kukacka, L.E.

    1985-08-01

    The primary goal of the geothermal materials program is to ensure that the private sector development of geothermal energy resources is not constrained by the availability of technologically and economically viable materials of construction. This requires the performance of long-term high risk GHTD-sponsored materials R and D. Ongoing programs described include high temperature elastomers for dynamic sealing applications, advanced materials for lost circulation control, waste utilization and disposal, corrosion resistant elastomeric liners for well casing, and non-metallic heat exchangers. 9 refs.

  3. NASA Thermographic Inspection of Advanced Composite Materials

    NASA Technical Reports Server (NTRS)

    Cramer, K. Elliott

    2004-01-01

    As the use of advanced composite materials continues to increase in the aerospace community, the need for a quantitative, rapid, in situ inspection technology has become a critical concern throughout the industry. In many applications it is necessary to monitor changes in these materials over an extended period of time to determine the effects of various load conditions. Additionally, the detection and characterization of defects such as delaminations, is of great concern. This paper will present the application of infrared thermography to characterize various composite materials and show the advantages of different heat source types. Finally, various analysis methodologies used for quantitative material property characterization will be discussed.

  4. Advanced superconducting materials for electronic applications

    NASA Astrophysics Data System (ADS)

    Beasley, M. R.

    1980-10-01

    Developments in the fabrication of tunnel junctions using Nb- and V-base transition-metal compounds and alloys are summarized. Particular attention is given to the advances in codeposition of these refractory high-transition-temperature superconductors and the properties of thin films deposited by the dual-electron-beam coevaporation technique. Problems associated with these materials are identified, and prospects for the future are discussed. Of the materials reviewed, Nb3Sn is singled out as one deserving further development.

  5. Property Data Summaries for Advanced Materials

    National Institute of Standards and Technology Data Gateway

    SRD 150 NIST Property Data Summaries for Advanced Materials (Web, free access)   Property Data Summaries are topical collections of property values derived from surveys of published data. Thermal, mechanical, structural, and chemical properties are included in the collections.

  6. Spacecraft Impacts with Advanced Power and Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Mason, Lee S.; Oleson, Steven R.

    2000-01-01

    A study was performed to assess the benefits of advanced power and electric propulsion systems for various space missions. Advanced power technologies that were considered included multiband gap and thin-film solar arrays, lithium batteries, and flywheels. Electric propulsion options included Hall effect thrusters and Ion thrusters. Several mission case studies were selected as representative of future applications for advanced power and propulsion systems. These included a low altitude Earth science satellite, a LEO communications constellation, a GEO military surveillance satellite, and a Mercury planetary mission. The study process entailed identification of overall mission performance using state-of-the-art power and propulsion technology, enhancements made possible with either power or electric propulsion advances individually, and the collective benefits realized when advanced power and electric propulsion are combined. Impacts to the overall spacecraft included increased payload, longer operational life, expanded operations and launch vehicle class step-downs.

  7. Advanced materials for solid oxide fuel cells

    SciTech Connect

    Armstrong, T.R.; Stevenson, J.

    1995-08-01

    The purpose of this research is to improve the properties of the current state-of-the-art materials used for solid oxide fuel cells (SOFCs). The objectives are to: (1) develop materials based on modifications of the state-of-the-art materials; (2) minimize or eliminate stability problems in the cathode, anode, and interconnect; (3) Electrochemically evaluate (in reproducible and controlled laboratory tests) the current state-of-the-art air electrode materials and cathode/electrolyte interfacial properties; (4) Develop accelerated electrochemical test methods to evaluate the performance of SOFCs under controlled and reproducible conditions; and (5) Develop and test materials for use in low-temperature SOFCs. The goal is to modify and improve the current state-of-the-art materials and minimize the total number of cations in each material to avoid negative effects on the materials properties. Materials to reduce potential deleterious interactions, (3) improve thermal, electrical, and electrochemical properties, (4) develop methods to synthesize both state-of-the-art and alternative materials for the simultaneous fabricatoin and consolidation in air of the interconnections and electrodes with the solid electrolyte, and (5) understand electrochemical reactions at materials interfaces and the effects of component composition and processing on those reactions.

  8. Advanced Industrial Materials (AIM) fellowship program

    SciTech Connect

    McCleary, D.D.

    1997-04-01

    The Advanced Industrial Materials (AIM) Program administers a Graduate Fellowship Program focused toward helping students who are currently under represented in the nation`s pool of scientists and engineers, enter and complete advanced degree programs. The objectives of the program are to: (1) establish and maintain cooperative linkages between DOE and professors at universities with graduate programs leading toward degrees or with degree options in Materials Science, Materials Engineering, Metallurgical Engineering, and Ceramic Engineering, the disciplines most closely related to the AIM Program at Oak Ridge National Laboratory (ORNL); (2) strengthen the capabilities and increase the level of participation of currently under represented groups in master`s degree programs, and (3) offer graduate students an opportunity for practical research experience related to their thesis topic through the three-month research assignment or practicum at ORNL. The program is administered by the Oak Ridge Institute for Science and Education (ORISE).

  9. Composite Dielectric Materials for Electrical Switching

    SciTech Connect

    Modine, F.A.

    1999-04-25

    Composites that consist of a dielectric host containing a particulate conductor as a second phase are of interest for electrical switching applications. Such composites are "smart" materials that can function as either voltage or current limiters, and the difference in fimction depends largely upon whether the dielectric is filled to below or above the percolation threshold. It also is possible to combine current and voltage limiting in a single composite to make a "super-smart" material.

  10. Structural materials challenges for advanced reactor systems

    NASA Astrophysics Data System (ADS)

    Yvon, P.; Carré, F.

    2009-03-01

    Key technologies for advanced nuclear systems encompass high temperature structural materials, fast neutron resistant core materials, and specific reactor and power conversion technologies (intermediate heat exchanger, turbo-machinery, high temperature electrolytic or thermo-chemical water splitting processes, etc.). The main requirements for the materials to be used in these reactor systems are dimensional stability under irradiation, whether under stress (irradiation creep or relaxation) or without stress (swelling, growth), an acceptable evolution under ageing of the mechanical properties (tensile strength, ductility, creep resistance, fracture toughness, resilience) and a good behavior in corrosive environments (reactor coolant or process fluid). Other criteria for the materials are their cost to fabricate and to assemble, and their composition could be optimized in order for instance to present low-activation (or rapid desactivation) features which facilitate maintenance and disposal. These requirements have to be met under normal operating conditions, as well as in incidental and accidental conditions. These challenging requirements imply that in most cases, the use of conventional nuclear materials is excluded, even after optimization and a new range of materials has to be developed and qualified for nuclear use. This paper gives a brief overview of various materials that are essential to establish advanced systems feasibility and performance for in pile and out of pile applications, such as ferritic/martensitic steels (9-12% Cr), nickel based alloys (Haynes 230, Inconel 617, etc.), oxide dispersion strengthened ferritic/martensitic steels, and ceramics (SiC, TiC, etc.). This article gives also an insight into the various natures of R&D needed on advanced materials, including fundamental research to investigate basic physical and chemical phenomena occurring in normal and accidental operating conditions, lab-scale tests to characterize candidate materials

  11. Development and evaluation of magnetic and electrical materials capable of operating in the 800 to 1600 F temperature range

    NASA Technical Reports Server (NTRS)

    Kueser, P. E.; Toth, J. W.

    1973-01-01

    The results are summarized of a research program on electrical materials for advanced space electric power systems. The areas investigated included improved high-temperature magnetic materials, high-temperature capacitor materials, ceramic-to-metal bore-seal technology, and simulated-space environmental testing of electric-power system components

  12. Recent Advances in Electric Sail Development

    NASA Astrophysics Data System (ADS)

    Janhunen, P.

    2009-04-01

    The electric solar wind sail is a newly invented way for using the solar wind dynamic pressure for providing thrust for a spacecraft. An electric sail spacecraft deploys long, thin, conducting tethers which are centrifugally stretched and kept in a high positive potential by a continuously working onboard electron gun. A positively charged wire embedded in solar wind plasma produces a Debye sheath around itself. Inside the sheath, the wire electric field repels solar wind protons so that they are deflected from their originally straight trajectories and thereby give some of their momentum to the wire. The solar wind dynamic pressure (on average 2 nPa at 1 AU distance) is about 5000 times weaker than the radiation pressure of the Sun, but since the wire's Debye sheath can be more than million times larger than the wire's physical diameter, the electric sail can be a mass-efficient method of spacecraft propulsion. If realised, the Electric Sail will be a significant and direct technical utilisation of a naturally occurring space plasma flow. We give an overview of the present status of the Electric Sail effort, reviewing its plasma physical basis and some technical aspects and potential applications. One application for the Electric Sail could be to implement the Interstellar Heliopause Probe, that is, a flight across the heliopause with less than 20-25 years of traveltime.

  13. Advanced Power Electronics and Electric Motors Annual Report -- 2013

    SciTech Connect

    Narumanchi, S.; Bennion, K.; DeVoto, D.; Moreno, G.; Rugh, J.; Waye, S.

    2015-01-01

    This report describes the research into advanced liquid cooling, integrated power module cooling, high temperature air cooled power electronics, two-phase cooling for power electronics, and electric motor thermal management by NREL's Power Electronics group in FY13.

  14. Advanced Material Strategies for Tissue Engineering Scaffolds

    PubMed Central

    Engelmayr, George C.; Borenstein, Jeffrey T.; Moutos, Franklin T.; Guilak, Farshid

    2010-01-01

    Tissue engineering seeks to restore the function of diseased or damaged tissues through the use of cells and biomaterial scaffolds. It is now apparent that the next generation of functional tissue replacements will require advanced material strategies to achieve many of the important requirements for long-term success. Here we provide representative examples of engineered skeletal and myocardial tissue constructs in which scaffolds were explicitly designed to match native tissue mechanical properties as well as to promote cell alignment. We discuss recent progress in microfluidic devices that can potentially serve as tissue engineering scaffolds, since mass transport via microvascular-like structures will be essential in the development of tissue engineered constructs on the length scale of native tissues. Given the rapid evolution of the field of tissue engineering, it is important to consider the use of advanced materials in light of the emerging role of genetics, growth factors, bioreactors, and other technologies. PMID:20882506

  15. Advanced fiber/matrix material systems

    NASA Technical Reports Server (NTRS)

    Hartness, J. Timothy

    1991-01-01

    Work completed in Phase 1 of the NASA Advanced Composite Technology program is discussed. Two towpreg forms (commingled yarns and fused powder towpregs) are being characterized under the program. These towpregs will be used to evaluate textile fabrication technologies for advanced aircraft composite structures. The unique characteristic of both of these material forms is that both fiber and matrix resin are handled in a single operation such as weaving, braiding, or fiber placement. The evaluation of both commingled and fused powder towpreg is described. Various polymer materials are considered for both subsonic and supersonic applications. Polymers initially being evaluated include thermoplastic polyimides such as Larc-TPI and New-TPI, thermoplastics such as PEEK and PEKEKK as well as some toughened crosslinked polyimides. Preliminary mechanical properties as well as tow handling are evaluated.

  16. Advanced Ceramic Materials for Future Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Misra, Ajay

    2015-01-01

    With growing trend toward higher temperature capabilities, lightweight, and multifunctionality, significant advances in ceramic matrix composites (CMCs) will be required for future aerospace applications. The presentation will provide an overview of material requirements for future aerospace missions, and the role of ceramics and CMCs in meeting those requirements. Aerospace applications will include gas turbine engines, aircraft structure, hypersonic and access to space vehicles, space power and propulsion, and space communication.

  17. Advanced materials for space nuclear power systems

    SciTech Connect

    Titran, R.H.; Grobstein, T.L. . Lewis Research Center); Ellis, D.L. )

    1991-01-01

    Research on monolithic refractory metal alloys and on metal matrix composites is being conducted at the NASA Lewis Research Center, Cleveland, Ohio, in support of advanced space power systems. The overall philosophy of the research is to develop and characterize new high-temperature power conversion and radiator materials and to provide spacecraft designers with material selection options and design information. Research on three candidate materials (carbide strengthened niobium alloy PWC-11 for fuel cladding, graphite fiber reinforced copper matrix composites (Gr/Cu) for heat rejection fins, and tungsten fiber reinforced niobium matrix composites (W/NB) for fuel containment and structural supports) considered for space power system applications is discussed. Each of these types of materials offers unique advantages for space power applications.

  18. Library of Advanced Materials for Engineering : LAME.

    SciTech Connect

    Hammerand, Daniel Carl; Scherzinger, William Mark

    2007-08-01

    Constitutive modeling is an important aspect of computational solid mechanics. Sandia National Laboratories has always had a considerable effort in the development of constitutive models for complex material behavior. However, for this development to be of use the models need to be implemented in our solid mechanics application codes. In support of this important role, the Library of Advanced Materials for Engineering (LAME) has been developed in Engineering Sciences. The library allows for simple implementation of constitutive models by model developers and access to these models by application codes. The library is written in C++ and has a very simple object oriented programming structure. This report summarizes the current status of LAME.

  19. Advanced Thermoelectric Materials for Radioisotope Thermoelectric Generators

    NASA Technical Reports Server (NTRS)

    Caillat, Thierry; Hunag, C.-K.; Cheng, S.; Chi, S. C.; Gogna, P.; Paik, J.; Ravi, V.; Firdosy, S.; Ewell, R.

    2008-01-01

    This slide presentation reviews the progress and processes involved in creating new and advanced thermoelectric materials to be used in the design of new radioiootope thermoelectric generators (RTGs). In a program with Department of Energy, NASA is working to develop the next generation of RTGs, that will provide significant benefits for deep space missions that NASA will perform. These RTG's are planned to be capable of delivering up to 17% system efficiency and over 12 W/kg specific power. The thermoelectric materials being developed are an important step in this process.

  20. Advanced research workshop: nuclear materials safety

    SciTech Connect

    Jardine, L J; Moshkov, M M

    1999-01-28

    The Advanced Research Workshop (ARW) on Nuclear Materials Safety held June 8-10, 1998, in St. Petersburg, Russia, was attended by 27 Russian experts from 14 different Russian organizations, seven European experts from six different organizations, and 14 U.S. experts from seven different organizations. The ARW was conducted at the State Education Center (SEC), a former Minatom nuclear training center in St. Petersburg. Thirty-three technical presentations were made using simultaneous translations. These presentations are reprinted in this volume as a formal ARW Proceedings in the NATO Science Series. The representative technical papers contained here cover nuclear material safety topics on the storage and disposition of excess plutonium and high enriched uranium (HEU) fissile materials, including vitrification, mixed oxide (MOX) fuel fabrication, plutonium ceramics, reprocessing, geologic disposal, transportation, and Russian regulatory processes. This ARW completed discussions by experts of the nuclear materials safety topics that were not covered in the previous, companion ARW on Nuclear Materials Safety held in Amarillo, Texas, in March 1997. These two workshops, when viewed together as a set, have addressed most nuclear material aspects of the storage and disposition operations required for excess HEU and plutonium. As a result, specific experts in nuclear materials safety have been identified, know each other from their participation in t he two ARW interactions, and have developed a partial consensus and dialogue on the most urgent nuclear materials safety topics to be addressed in a formal bilateral program on t he subject. A strong basis now exists for maintaining and developing a continuing dialogue between Russian, European, and U.S. experts in nuclear materials safety that will improve the safety of future nuclear materials operations in all the countries involved because of t he positive synergistic effects of focusing these diverse backgrounds of

  1. Implications of smart materials in advanced prosthetics

    NASA Astrophysics Data System (ADS)

    Lenoe, Edward M.; Radicic, William N.; Knapp, Michael S.

    1994-05-01

    This research reviews common implant materials and suggests smart materials that may be used as substitutes. Current prosthetic technology, including artificial limbs, joints, and soft and hard tissue, falls short in comprehensive characterization of the chemo-mechanics and materials relationships of the natural tissues and their prosthetic materials counterparts. Many of these unknown chemo-mechanical properties in natural tissue systems maintain cooperative function that allows for optimum efficiency in performance and healing. Traditional prosthetic devices have not taken into account the naturally occurring electro-chemo-mechanical stress- strain relationships that normally exist in a tissue system. Direct mechanical deformation of tissue and cell membrane as a possible use of smart materials may lead to improved prosthetic devices once the mechanosensory systems in living tissues are identified and understood. Smart materials may aid in avoiding interfacial atrophy which is a common cause of prosthetic failure. Finally, we note that advanced composite materials have not received sufficient attention, they should be more widely used in prosthetics. Their structural efficiency allows design and construction of truly efficient bionic devices.

  2. Advanced batteries for electric vehicle applications

    SciTech Connect

    Henriksen, G.L.

    1993-08-01

    A technology assessment is given for electric batteries with potential for use in electric powered vehicles. Parameters considered include: specific energy, specific power, energy density, power density, cycle life, service life, recharge time, and selling price. Near term batteries include: nickel/cadmium and lead-acid batteries. Mid term batteries include: sodium/sulfur, sodium/nickel chloride, nickel/metal hydride, zinc/air, zinc/bromine, and nickel/iron systems. Long term batteries include: lithium/iron disulfide and lithium- polymer systems. Performance and life testing data for these systems are discussed. (GHH)

  3. Electrical research on solar cells and photovoltaic materials

    NASA Technical Reports Server (NTRS)

    Orehotsky, J.

    1985-01-01

    A systematic study of the properties of various polymer pottant materials and of the electrochemical corrosion mechanisms in solar cell materials is required for advancing the technology of terrestrial photovoltaic modules. The items of specific concern in this sponsored research activity involve: (1) kinetics of plasticizer loss in PVB, (2) kinetics of water absorption and desorption in PVB, (3) kinetics of water absorption and desorption in EVA, (4) the electrical properties at PVB as a function of temperature and humidity, (5) the electrical properties of EVA as a function of temperature and humidity, (6) solar cell corrosion characteristics, (7) water absorption effects in PVB and EVA, and (8) ion implantation and radiation effects in PVB and EVA.

  4. Recent advances in organic semiconducting materials

    NASA Astrophysics Data System (ADS)

    Ostroverkhova, Oksana

    2011-10-01

    Organic semiconductors have attracted attention due to their low cost, easy fabrication, and tunable properties. Applications of organic materials in thin-film transistors, solar cells, light-emitting diodes, sensors, and many other devices have been actively explored. Recent advances in organic synthesis, material processing, and device fabrication led to significant improvements in (opto)electronic device performance. However, a number of challenges remain. These range from lack of understanding of basic physics of intermolecular interactions that determine optical and electronic properties of organic materials to difficulties in controlling film morphology and stability. In this presentation, current state of the field will be reviewed and recent results related to charge carrier and exciton dynamics in organic thin films will be presented.[4pt] In collaboration with Whitney Shepherd, Mark Kendrick, Andrew Platt, Oregon State University; Marsha Loth and John Anthony, University of Kentucky.

  5. Electron energy loss spectroscopy in advanced materials

    SciTech Connect

    Zaluzec, N.J.

    1991-01-01

    The combination of a Transmission Electron Microscope (TEM) with an electron energy loss spectrometer (EELS) yields a powerful tool for the microcharacterization of materials. However, the application of this technique to advanced materials problems can only be fully appreciated when the information obtained using EELS is related to that obtained from other analytical spectroscopies. In this chapter, we briefly discuss the relative performance of X-ray, Auger and Photoelectron Spectroscopies with EELS pointing out the limitations and merits of each. This comparison is followed by examples of the application of EELS to investigations involving high {Tc} superconductors, artificial metallic superlattices, amorphous magnetic materials and the characterization of metallic hydride phases. 14 refs., 22 figs.

  6. Automotive applications for advanced composite materials

    NASA Technical Reports Server (NTRS)

    Deutsch, G. C.

    1978-01-01

    A description is presented of nonaerospace applications for advanced composite materials with special emphasis on the automotive applications. The automotive industry has to satisfy exacting requirements to reduce the average fuel consumption of cars. A feasible approach to accomplish this involves the development of composites cars with a total weight of 2400 pounds and a fuel consumption of 33 miles per gallon. In connection with this possibility, the automotive companies have started to look seriously at composite materials. The aerospace industry has over the past decade accumulated a considerable data base on composite materials and this is being made available to the nonaerospace sector. However, the automotive companies will place prime emphasis on low cost resins which lend themselves to rapid fabrication techniques.

  7. International Symposium on Advanced Materials (ISAM 2013)

    NASA Astrophysics Data System (ADS)

    2014-06-01

    This proceeding is a compilation of peer reviewed papers presented at the 13th International Symposium on Advanced Materials (ISAM 2013) held from September 23-27, 2013, at Islamabad, Pakistan. In my capacity as ISAM-2013 Secretary, I feel honoured that the symposium has ended on a positive note. The ever increasing changes and intricacies that characterize modern industry necessitate a growing demand for technical information on advanced materials. ISAM and other similar forums serve to fulfill this need. The five day deliberations of ISAM 2013, consisted of 19 technical sessions and 2 poster sessions. In all, 277 papers were presented, inclusive of 80 contributory, invited and oral presentations. The symposium also hosted panel discussions led by renowned scientists and eminent researchers from foreign as well as local institutes. The ultimate aim of this proceeding is to record in writing the new findings in the field of advanced materials. I hope that the technical data available in this publication proves valuable to young scientists and researchers working in this area of science. At the same time, I wish to acknowledge Institute of Physics (IOP) Publishing UK, for accepting the research papers from ISAM-2013 for publication in the IOP Conference Series: Materials Science and Engineering. The proceeding will be available on the IOP website as an online open access document. I am profoundly thankful to the Symposium Chairman for his steadfast support and valuable guidance without which ISAM 2013 could not have been the mega event that it turned out to be. My gratitude to all our distinguished participants, session chairs/co-chairs, and reviewers for their active role in the symposium. I appreciate the entire organizing committee for the zest and ardor with which each committee fulfilled its obligations to ISAM. Last yet not the least, my thankfulness goes to all our sponsors for wilfully financing the event. Dr. Sara Qaisar Symposium Secretary Further

  8. The General Electric Advanced Course in Engineering.

    ERIC Educational Resources Information Center

    Mack, Donald R.

    A three-year, in-house engineering course offered to selected General Electric Company engineers is discussed. It is designed to develop the ability to identify and solve real engineering problems. The course may be taken concurrently with college courses in a cooperative program that can result in a graduate degree in engineering. (MLH)

  9. Crashworthiness analysis using advanced material models in DYNA3D

    SciTech Connect

    Logan, R.W.; Burger, M.J.; McMichael, L.D.; Parkinson, R.D.

    1993-10-22

    As part of an electric vehicle consortium, LLNL and Kaiser Aluminum are conducting experimental and numerical studies on crashworthy aluminum spaceframe designs. They have jointly explored the effect of heat treat on crush behavior and duplicated the experimental behavior with finite-element simulations. The major technical contributions to the state of the art in numerical simulation arise from the development and use of advanced material model descriptions for LLNL`s DYNA3D code. Constitutive model enhancements in both flow and failure have been employed for conventional materials such as low-carbon steels, and also for lighter weight materials such as aluminum and fiber composites being considered for future vehicles. The constitutive model enhancements are developed as extensions from LLNL`s work in anisotropic flow and multiaxial failure modeling. Analysis quality as a function of level of simplification of material behavior and mesh is explored, as well as the penalty in computation cost that must be paid for using more complex models and meshes. The lightweight material modeling technology is being used at the vehicle component level to explore the safety implications of small neighborhood electric vehicles manufactured almost exclusively from these materials.

  10. ASME Material Challenges for Advanced Reactor Concepts

    SciTech Connect

    Piyush Sabharwall; Ali Siahpush

    2013-07-01

    This study presents the material Challenges associated with Advanced Reactor Concept (ARC) such as the Advanced High Temperature Reactor (AHTR). ACR are the next generation concepts focusing on power production and providing thermal energy for industrial applications. The efficient transfer of energy for industrial applications depends on the ability to incorporate cost-effective heat exchangers between the nuclear heat transport system and industrial process heat transport system. The heat exchanger required for AHTR is subjected to a unique set of conditions that bring with them several design challenges not encountered in standard heat exchangers. The corrosive molten salts, especially at higher temperatures, require materials throughout the system to avoid corrosion, and adverse high-temperature effects such as creep. Given the very high steam generator pressure of the supercritical steam cycle, it is anticipated that water tube and molten salt shell steam generators heat exchanger will be used. In this paper, the ASME Section III and the American Society of Mechanical Engineers (ASME) Section VIII requirements (acceptance criteria) are discussed. Also, the ASME material acceptance criteria (ASME Section II, Part D) for high temperature environment are presented. Finally, lack of ASME acceptance criteria for thermal design and analysis are discussed.

  11. ARPA-E: Advancing the Electric Grid

    ScienceCinema

    Lemmon, John; Ruiz, Pablo; Sommerer, Tim; Aziz, Michael

    2014-03-13

    The electric grid was designed with the assumption that all energy generation sources would be relatively controllable, and grid operators would always be able to predict when and where those sources would be located. With the addition of renewable energy sources like wind and solar, which can be installed faster than traditional generation technologies, this is no longer the case. Furthermore, the fact that renewable energy sources are imperfectly predictable means that the grid has to adapt in real-time to changing patterns of power flow. We need a dynamic grid that is far more flexible. This video highlights three ARPA-E-funded approaches to improving the grid's flexibility: topology control software from Boston University that optimizes power flow, gas tube switches from General Electric that provide efficient power conversion, and flow batteries from Harvard University that offer grid-scale energy storage.

  12. ARPA-E: Advancing the Electric Grid

    SciTech Connect

    Lemmon, John; Ruiz, Pablo; Sommerer, Tim; Aziz, Michael

    2014-02-24

    The electric grid was designed with the assumption that all energy generation sources would be relatively controllable, and grid operators would always be able to predict when and where those sources would be located. With the addition of renewable energy sources like wind and solar, which can be installed faster than traditional generation technologies, this is no longer the case. Furthermore, the fact that renewable energy sources are imperfectly predictable means that the grid has to adapt in real-time to changing patterns of power flow. We need a dynamic grid that is far more flexible. This video highlights three ARPA-E-funded approaches to improving the grid's flexibility: topology control software from Boston University that optimizes power flow, gas tube switches from General Electric that provide efficient power conversion, and flow batteries from Harvard University that offer grid-scale energy storage.

  13. Advanced Technology Composite Fuselage - Materials and Processes

    NASA Technical Reports Server (NTRS)

    Scholz, D. B.; Dost, E. F.; Flynn, B. W.; Ilcewicz, L. B.; Nelson, K. M.; Sawicki, A. J.; Walker, T. H.; Lakes, R. S.

    1997-01-01

    The goal of Boeing's Advanced Technology Composite Aircraft Structures (ATCAS) program was to develop the technology required for cost and weight efficient use of composite materials in transport fuselage structure. This contractor report describes results of material and process selection, development, and characterization activities. Carbon fiber reinforced epoxy was chosen for fuselage skins and stiffening elements and for passenger and cargo floor structures. The automated fiber placement (AFP) process was selected for fabrication of monolithic and sandwich skin panels. Circumferential frames and window frames were braided and resin transfer molded (RTM'd). Pultrusion was selected for fabrication of floor beams and constant section stiffening elements. Drape forming was chosen for stringers and other stiffening elements. Significant development efforts were expended on the AFP, braiding, and RTM processes. Sandwich core materials and core edge close-out design concepts were evaluated. Autoclave cure processes were developed for stiffened skin and sandwich structures. The stiffness, strength, notch sensitivity, and bearing/bypass properties of fiber-placed skin materials and braided/RTM'd circumferential frame materials were characterized. The strength and durability of cocured and cobonded joints were evaluated. Impact damage resistance of stiffened skin and sandwich structures typical of fuselage panels was investigated. Fluid penetration and migration mechanisms for sandwich panels were studied.

  14. Advanced High-Temperature Engine Materials Technology Progresses

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The objective of the Advanced High Temperature Engine Materials Technology Program (HITEMP) is to generate technology for advanced materials and structural analysis that will increase fuel economy, improve reliability, extend life, and reduce operating costs for 21st century civil propulsion systems. The primary focus is on fan and compressor materials (polymer-matrix composites--PMC's), compressor and turbine materials (superalloys, and metal-matrix and intermetallic-matrix composites--MMC's and IMC's) and turbine materials (ceramic-matrix composites--CMC's). These advanced materials are being developed by in-house researchers and on grants and contracts. NASA considers this program to be a focused materials and structures research effort that builds on our base research programs and supports component-development projects. HITEMP is coordinated with the Advanced Subsonic Technology (AST) Program and the Department of Defense/NASA Integrated High-Performance Turbine Engine Technology (IHPTET) Program. Advanced materials and structures technologies from HITEMP may be used in these future applications. Recent technical accomplishments have not only improved the state-of-the-art but have wideranging applications to industry. A high-temperature thin-film strain gage was developed to measure both dynamic and static strain up to 1100 C (2000 F). The gage's unique feature is that it is minimally intrusive. This technology, which received a 1995 R&D 100 Award, has been transferred to AlliedSignal Engines, General Electric Company, and Ford Motor Company. Analytical models developed at the NASA Lewis Research Center were used to study Textron Specialty Materials' manufacturing process for titanium-matrix composite rings. Implementation of our recommendations on tooling and processing conditions resulted in the production of defect free rings. In the Lincoln Composites/AlliedSignal/Lewis cooperative program, a composite compressor case is being manufactured with a Lewis

  15. Advances in electrode materials for AMTEC

    NASA Astrophysics Data System (ADS)

    Ryan, M. A.; Williams, R. M.; Lara, L.; Fiebig, B. G.; Cortez, R. H.; Kisor, A. K.; Shields, V. B.; Homer, M. L.

    2001-02-01

    A mixed conducting electrode for the Alkali Metal Thermal to Electric Converter (AMTEC) has been made and tested. The electrode is made from a slurry of metal and TiO2 powders which is applied to the electrolyte and fired to sinter the electrode material. During the first 48-72 hours of operation in a SETC, the electrode takes up Na from low pressure sodium vapor to make a metal-Na-Ti-O compound. This compound is electronically conducting and ionically conducting to sodium; electronic conduction is also provided by the metal in the electrode. With a mixed conducting electrode made from robust, low vapor pressure materials, the promise for improved performance and lifetime is high. .

  16. Advanced Materials Laboratory User Test Planning Guide

    NASA Technical Reports Server (NTRS)

    Orndoff, Evelyne

    2012-01-01

    Test process, milestones and inputs are unknowns to first-time users of the Advanced Materials Laboratory. The User Test Planning Guide aids in establishing expectations for both NASA and non-NASA facility customers. The potential audience for this guide includes both internal and commercial spaceflight hardware/software developers. It is intended to assist their test engineering personnel in test planning and execution. Material covered includes a roadmap of the test process, roles and responsibilities of facility and user, major milestones, facility capabilities, and inputs required by the facility. Samples of deliverables, test article interfaces, and inputs necessary to define test scope, cost, and schedule are included as an appendix to the guide.

  17. Development of advanced composite ceramic tool material

    SciTech Connect

    Huang Chuanzhen; Ai Xing

    1996-08-01

    An advanced ceramic cutting tool material has been developed by means of silicon carbide whisker (SiCw) reinforcement and silicon carbide particle (SiCp) dispersion. The material has the advantage of high bending strength and fracture toughness. Compared with the mechanical properties of Al{sub 2}O{sub 3}/SiCp(AP), Al{sub 2}O{sub 3}/SiCw(JX-1), and Al{sub 2}O{sub 3}/SiCp/SiCw(JX-2-I), it confirms that JX-2-I composites have obvious additive effects of both reinforcing and toughening. The reinforcing and toughening mechanisms of JX-2-I composites were studied based on the analysis of thermal expansion mismatch and the observation of microstructure. The cutting performance of JX-2-I composites was investigated primarily.

  18. On the fracture toughness of advanced materials

    SciTech Connect

    Launey, Maximilien E.; Ritchie, Robert O.

    2008-11-24

    Few engineering materials are limited by their strength; rather they are limited by their resistance to fracture or fracture toughness. It is not by accident that most critical structures, such as bridges, ships, nuclear pressure vessels and so forth, are manufactured from materials that are comparatively low in strength but high in toughness. Indeed, in many classes of materials, strength and toughness are almost mutually exclusive. In the first instance, such resistance to fracture is a function of bonding and crystal structure (or lack thereof), but can be developed through the design of appropriate nano/microstructures. However, the creation of tough microstructures in structural materials, i.e., metals, polymers, ceramics and their composites, is invariably a compromise between resistance to intrinsic damage mechanisms ahead of the tip of a crack (intrinsic toughening) and the formation of crack-tip shielding mechanisms which principally act behind the tip to reduce the effective 'crack-driving force' (extrinsic toughening). Intrinsic toughening is essentially an inherent property of a specific microstructure; it is the dominant form of toughening in ductile (e.g., metallic) materials. However, for most brittle (e.g., ceramic) solids, and this includes many biological materials, it is largely ineffective and toughening conversely must be developed extrinsically, by such shielding mechanisms as crack bridging. From a fracture mechanics perspective, this results in toughening in the form of rising resistance-curve behavior where the fracture resistance actually increases with crack extension. The implication of this is that in many biological and high-strength advanced materials, toughness is developed primarily during crack growth and not for crack initiation. This is an important realization yet is still rarely reflected in the way that toughness is measured, which is invariably involves the use of single-value (crack-initiation) parameters such as the

  19. Improved Thermoelectric Devices: Advanced Semiconductor Materials for Thermoelectric Devices

    SciTech Connect

    2009-12-11

    Broad Funding Opportunity Announcement Project: Phononic Devices is working to recapture waste heat and convert it into usable electric power. To do this, the company is using thermoelectric devices, which are made from advanced semiconductor materials that convert heat into electricity or actively remove heat for refrigeration and cooling purposes. Thermoelectric devices resemble computer chips, and they manage heat by manipulating the direction of electrons at the nanoscale. These devices aren’t new, but they are currently too inefficient and expensive for widespread use. Phononic Devices is using a high-performance, cost-effective thermoelectric design that will improve the device’s efficiency and enable electronics manufacturers to more easily integrate them into their products.

  20. NREL Advances Spillover Materials for Hydrogen Storage (Fact Sheet)

    SciTech Connect

    Not Available

    2010-12-01

    This fact sheet describes NREL's accomplishments in advancing spillover materials for hydrogen storage and improving the reproducible synthesis, long-term durability, and material costs of hydrogen storage materials. Work was performed by NREL's Chemical and Materials Science Center.

  1. Advanced ac powertrain for electric vehicles

    SciTech Connect

    Slicker, J.M.; Kalns, L.

    1985-01-01

    The design of an ac propulsion system for an electric vehicle includes a three-phase induction motor, transistorized PWM inverter/battery charger, microprocessor-based controller, and two-speed automatic transaxle. This system was built and installed in a Mercury Lynx test bed vehicle as part of a Department of Energy propulsion system development program. An integral part of the inverter is a 4-kw battery charger which utilizes one of the bridge transistors. The overall inverter strategy for this configuration is discussed. The function of the microprocessor-based controller is described. Typical test results of the total vehicle and each of its major components are given, including system efficiencies and test track performance results.

  2. Advanced electric motor technology: Flux mapping

    NASA Technical Reports Server (NTRS)

    Doane, George B., III; Campbell, Warren; Brantley, Larry W.; Dean, Garvin

    1992-01-01

    This report contains the assumptions, mathematical models, design methodology, and design points involved with the design of an electromechanical actuator (EMA) suitable for directing the thrust vector of a large MSFC/NASA launch vehicle. Specifically the design of such an actuator for use on the upcoming liquid fueled National Launch System (NLS) is considered culminating in a point design of both the servo system and the electric motor needed. A major thrust of the work is in selecting spur gear and roller screw reduction ratios to achieve simultaneously wide bandwidth, maximum power transfer, and disturbance rejection while meeting specified horsepower requirements at a given stroking speed as well as a specified maximum stall force. An innovative feedback signal is utilized in meeting these diverse objectives.

  3. Advanced power electronics and electric machinery program

    SciTech Connect

    None, None

    2007-12-01

    The U.S. Department of Energy (DOE) and the U.S. Council for Automotive Research (composed of automakers Ford, General Motors, and Chrysler) announced in January 2002 a new cooperative research effort. Known as "FreedomCAR" (derived from "Freedom" and "Cooperative Automotive Research"), it represents DOE's commitment to developing public/private partnerships to fund high-risk, high-payoff research into advanced automotive technologies. Efficient fuel cell technology, which uses hydrogen to power automobiles without air pollution, is a very promising pathway to achieving the ultimate vision. The new partnership replaces and builds upon the Partnership for a New Generation of Vehicles initiative that ran from 1993 through 2001.

  4. Advanced electric propulsion system concept for electric vehicles

    NASA Technical Reports Server (NTRS)

    Raynard, A. E.; Forbes, F. E.

    1979-01-01

    Seventeen propulsion system concepts for electric vehicles were compared to determine the differences in components and battery pack to achieve the basic performance level. Design tradeoffs were made for selected configurations to find the optimum component characteristics required to meet all performance goals. The anticipated performance when using nickel-zinc batteries rather than the standard lead-acid batteries was also evaluated. The two systems selected for the final conceptual design studies included a system with a flywheel energy storage unit and a basic system that did not have a flywheel. The flywheel system meets the range requirement with either lead-acid or nickel-zinc batteries and also the acceleration of zero to 89 km/hr in 15 s. The basic system can also meet the required performance with a fully charged battery, but, when the battery approaches 20 to 30 percent depth of discharge, maximum acceleration capability gradually degrades. The flywheel system has an estimated life-cycle cost of $0.041/km using lead-acid batteries. The basic system has a life-cycle cost of $0.06/km. The basic system, using batteries meeting ISOA goals, would have a life-cycle cost of $0.043/km.

  5. Characterization and damage evaluation of advanced materials

    NASA Astrophysics Data System (ADS)

    Mitrovic, Milan

    Mechanical characterization of advanced materials, namely magnetostrictive and graphite/epoxy composite materials, is studied in this dissertation, with an emphasis on damage evaluation of composite materials. Consequently, the work in this dissertation is divided into two parts, with the first part focusing on characterization of the magneto-elastic response of magnetostrictlve materials, while the second part of this dissertation describes methods for evaluating the fatigue damage in composite materials. The objective of the first part of this dissertation is to evaluate a nonlinear constitutive relation which more closely depict the magneto-elastic response of magnetostrictive materials. Correlation between experimental and theoretical values indicate that the model adequately predicts the nonlinear strain/field relations in specific regimes, and that the currently employed linear approaches are inappropriate for modeling the response of this material in a structure. The objective of the second part of this dissertation is to unravel the complexities associated with damage events associated with polymeric composite materials. The intent is to characterize and understand the influence of impact and fatigue induced damage on the residual thermo-mechanical properties and compressive strength of composite systems. The influence of fatigue generated matrix cracking and micro-delaminations on thermal expansion coefficient (TEC) and compressive strength is investigated for woven graphite/epoxy composite system. Experimental results indicate that a strong correlation exists between TEC and compressive strength measurements, indicating that TEC measurements can be used as a damage metric for this material systems. The influence of delaminations on the natural frequencies and mode shapes of a composite laminate is also investigated. Based on the changes of these parameters as a function of damage, a methodology for determining the size and location of damage is suggested

  6. Continuously variable transmission: Assessment of applicability to advance electric vehicles

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.; Parker, R. J.

    1981-01-01

    A brief historical account of the evolution of continuously variable transmissions (CVT) for automotive use is given. The CVT concepts which are potentially suitable for application with electric and hybrid vehicles are discussed. The arrangement and function of several CVT concepts are cited along with their current developmental status. The results of preliminary design studies conducted on four CVT concepts for use in advanced electric vehicles are discussed.

  7. Electrically conducting ternary amorphous fully oxidized materials and their application

    NASA Technical Reports Server (NTRS)

    Giauque, Pierre (Inventor); Nicolet, Marc (Inventor); Gasser, Stefan M. (Inventor); Kolawa, Elzbieta A. (Inventor); Cherry, Hillary (Inventor)

    2004-01-01

    Electrically active devices are formed using a special conducting material of the form Tm--Ox mixed with SiO2 where the materials are immiscible. The immiscible materials are forced together by using high energy process to form an amorphous phase of the two materials. The amorphous combination of the two materials is electrically conducting but forms an effective barrier.

  8. Electrical Arc Ignition Testing of Spacesuit Materials

    NASA Technical Reports Server (NTRS)

    Smith, Sarah; Gallus, Tim; Tapia, Susana; Ball, Elizabeth; Beeson, Harold

    2006-01-01

    A viewgraph presentation on electrical arc ignition testing of spacesuit materials is shown. The topics include: 1) Background; 2) Test Objectives; 3) Test Sample Materials; 4) Test Methods; 5) Scratch Test Objectives; 6) Cotton Scratch Test Video; 7) Scratch Test Results; 8) Entire Date Plot; 9) Closeup Data Plot; 10) Scratch Test Problems; 11) Poke Test Objectives; 12) Poke Test Results; 13) Poke Test Problems; 14) Wire-break Test Objectives; 15) Cotton Wire-Break Test Video; 16) High Speed Cotton Wire-break Test Video; 17) Typical Data Plot; 18) Closeup Data Plot; 19) Wire-break Test Results; 20) Wire-break Tests vs. Scratch Tests; 21) Urethane-coated Nylon; and 22) Moleskin.

  9. Advanced electric motor technology flux mapping

    NASA Technical Reports Server (NTRS)

    Doane, George B., III; Campbell, Warren; Dean, Garvin

    1993-01-01

    Design of electric motors which fulfill the needs of Thrust Vector Control (TVC) actuators used in large rocket propelled launch vehicles is covered. To accomplish this end the methodology of design is laid out in some detail. In addition a point design of a motor to fulfill the requirements of a certain actuator specified by MSFC is accomplished and reported upon. In the course of this design great stress has been placed on ridding the actuator of internally generated heat. To conduct the heat out of the motor use is made of the unique properties of the in house MSFC designed driving electronics. This property is that as along as they are operated in a quasi-linear mode the electronics nullify the effects of armature inductance as far as the phase of the armature current versus the rotor position is concerned. Actually the additional inductance due to the extended end turns in this design is of benefit because in the shorted armature failure mode the armature current in the fault (caused by the rotor flux sweeping past the armature) is diminished at a given rotor speed when compared to a more conventional motor with lower inductance. The magnetic circuit is analyzed using electromagnetic finite element methods.

  10. Polymers as advanced materials for desiccant applications

    SciTech Connect

    Czanderna, A.W.

    1990-12-01

    This research is concerned with solid materials used as desiccants for desiccant cooling systems (DCSs) that process water vapor in an atmosphere to produce cooling. Background information includes an introduction to DCSs and the role of the desiccant as a system component. The water vapor sorption performance criteria used for screening the modified polymers prepared include the water sorption capacity from 5% to 80% relative humidity (R.H.), isotherm shape, and rate of adsorption and desorption. Measurements are presented for the sorption performance of modified polymeric advanced desiccant materials with the quartz crystal microbalance. Isotherms of polystyrene sulfonic acid (PSSA) taken over a 5-month period show that the material has a dramatic loss in capacity and that the isotherm shape is time dependent. The adsorption and desorption kinetics for PSSA and all the ionic salts of it studied are easily fast enough for commercial DCS applications with a wheel rotation speed of 6 min per revolution. Future activities for the project are addressed, and a 5-year summary of the project is included as Appendix A. 34 refs., 20 figs., 3 tabs.

  11. Advanced continuously variable transmissions for electric and hybrid vehicles

    NASA Technical Reports Server (NTRS)

    Loewenthal, S. H.

    1980-01-01

    A brief survey of past and present continuously variable transmissions (CVT) which are potentially suitable for application with electric and hybrid vehicles is presented. Discussion of general transmission requirements and benefits attainable with a CVT for electric vehicle use is given. The arrangement and function of several specific CVT concepts are cited along with their current development status. Lastly, the results of preliminary design studies conducted under a NASA contract for DOE on four CVT concepts for use in advanced electric vehicles are reviewed.

  12. Thermal fatigue durability for advanced propulsion materials

    NASA Technical Reports Server (NTRS)

    Halford, Gary R.

    1989-01-01

    A review is presented of thermal and thermomechanical fatigue (TMF) crack initiation life prediction and cyclic constitutive modeling efforts sponsored recently by the NASA Lewis Research Center in support of advanced aeronautical propulsion research. A brief description is provided of the more significant material durability models that were created to describe TMF fatigue resistance of both isotropic and anisotropic superalloys, with and without oxidation resistant coatings. The two most significant crack initiation models are the cyclic damage accumulation model and the total strain version of strainrange partitioning. Unified viscoplastic cyclic constitutive models are also described. A troika of industry, university, and government research organizations contributed to the generation of these analytic models. Based upon current capabilities and established requirements, an attempt is made to project which TMF research activities most likely will impact future generation propulsion systems.

  13. Advanced Pattern Material for Investment Casting Applications

    SciTech Connect

    F. Douglas Neece Neil Chaudhry

    2006-02-08

    Cleveland Tool and Machine (CTM) of Cleveland, Ohio in conjunction with Harrington Product Development Center (HPDC) of Cincinnati, Ohio have developed an advanced, dimensionally accurate, temperature-stable, energy-efficient and cost-effective material and process to manufacture patterns for the investment casting industry. In the proposed technology, FOPAT (aFOam PATtern material) has been developed which is especially compatible with the investment casting process and offers the following advantages: increased dimensional accuracy; increased temperature stability; lower cost per pattern; less energy consumption per pattern; decreased cost of pattern making equipment; decreased tooling cost; increased casting yield. The present method for investment casting is "the lost wax" process, which is exactly that, the use of wax as a pattern material, which is then melted out or "lost" from the ceramic shell. The molten metal is then poured into the ceramic shell to produce a metal casting. This process goes back thousands of years and while there have been improvements in the wax and processing technology, the material is basically the same, wax. The proposed technology is based upon an established industrial process of "Reaction Injection Molding" (RIM) where two components react when mixed and then "molded" to form a part. The proposed technology has been modified and improved with the needs of investment casting in mind. A proprietary mix of components has been formulated which react and expand to form a foam-like product. The result is an investment casting pattern with smooth surface finish and excellent dimensional predictability along with the other key benefits listed above.

  14. Advanced materials for thermal protection system

    NASA Astrophysics Data System (ADS)

    Heng, Sangvavann; Sherman, Andrew J.

    1996-03-01

    Reticulated open-cell ceramic foams (both vitreous carbon and silicon carbide) and ceramic composites (SiC-based, both monolithic and fiber-reinforced) were evaluated as candidate materials for use in a heat shield sandwich panel design as an advanced thermal protection system (TPS) for unmanned single-use hypersonic reentry vehicles. These materials were fabricated by chemical vapor deposition/infiltration (CVD/CVI) and evaluated extensively for their mechanical, thermal, and erosion/ablation performance. In the TPS, the ceramic foams were used as a structural core providing thermal insulation and mechanical load distribution, while the ceramic composites were used as facesheets providing resistance to aerodynamic, shear, and erosive forces. Tensile, compressive, and shear strength, elastic and shear modulus, fracture toughness, Poisson's ratio, and thermal conductivity were measured for the ceramic foams, while arcjet testing was conducted on the ceramic composites at heat flux levels up to 5.90 MW/m2 (520 Btu/ft2ṡsec). Two prototype test articles were fabricated and subjected to arcjet testing at heat flux levels of 1.70-3.40 MW/m2 (150-300 Btu/ft2ṡsec) under simulated reentry trajectories.

  15. Indentation Methods in Advanced Materials Research Introduction

    SciTech Connect

    Pharr, George Mathews; Cheng, Yang-Tse; Hutchings, Ian; Sakai, Mototsugu; Moody, Neville; Sundararajan, G.; Swain, Michael V.

    2009-01-01

    Since its commercialization early in the 20th century, indentation testing has played a key role in the development of new materials and understanding their mechanical behavior. Progr3ess in the field has relied on a close marriage between research in the mechanical behavior of materials and contact mechanics. The seminal work of Hertz laid the foundations for bringing these two together, with his contributions still widely utilized today in examining elastic behavior and the physics of fracture. Later, the pioneering work of Tabor, as published in his classic text 'The Hardness of Metals', exapdned this understanding to address the complexities of plasticity. Enormous progress in the field has been achieved in the last decade, made possible both by advances in instrumentation, for example, load and depth-sensing indentation and scanning electron microscopy (SEM) and transmission electron microscopy (TEM) based in situ testing, as well as improved modeling capabilities that use computationally intensive techniques such as finite element analysis and molecular dynamics simulation. The purpose of this special focus issue is to present recent state of the art developments in the field.

  16. Advanced Materials in Support of EERE Needs to Advance Clean Energy Technologies Program Implementation

    SciTech Connect

    Liby, Alan L; Rogers, Hiram

    2013-10-01

    The goal of this activity was to carry out program implementation and technical projects in support of the ARRA-funded Advanced Materials in Support of EERE Needs to Advance Clean Energy Technologies Program of the DOE Advanced Manufacturing Office (AMO) (formerly the Industrial Technologies Program (ITP)). The work was organized into eight projects in four materials areas: strategic materials, structural materials, energy storage and production materials, and advanced/field/transient processing. Strategic materials included work on titanium, magnesium and carbon fiber. Structural materials included work on alumina forming austentic (AFA) and CF8C-Plus steels. The advanced batteries and production materials projects included work on advanced batteries and photovoltaic devices. Advanced/field/transient processing included work on magnetic field processing. Details of the work in the eight projects are available in the project final reports which have been previously submitted.

  17. Advanced Functional Materials for Energy Related Applications

    NASA Astrophysics Data System (ADS)

    Sasan, Koroush

    light. Finally, we demonstrate that open-framework chalcogenides can also be used as efficient photocatalysts for the reduction of CO2 to CH 4. These materials contain covalent superlattices of nanosized supertetrahedral clusters, which can be made with different metal cations to provide high electrical conductivity and current density as well as materials with different band gaps. The ability in incorporating different metal cations further enhances the material's photocatalytic activity, which could possibly provide alternative technologies for reducing CO2 in the atmosphere and simultaneously producing fuel.

  18. Abrasive wear of advanced structural materials

    NASA Astrophysics Data System (ADS)

    Lee, Gun-Young

    Wear of advanced structural materials, namely composites and ceramics, in abrasion has been examined in the present study. A simple physically-based model for the abrasive wear of composite materials is presented based on the mechanics and mechanisms associated with sliding wear in soft (ductile) matrix composites containing hard (brittle) reinforcement particles. The model is based on the assumption that any portion of the reinforcement that is removed as wear debris cannot contribute to the wear resistance of the matrix material. The size of this non-contributing portion of reinforcement is estimated by modeling three primary wear mechanisms, specifically plowing, cracking at the matrix/reinforcement interface or in the reinforcement, and particle removal. Critical variables describing the role of the reinforcement, such as the relative size, fracture toughness, and the nature of the matrix/reinforcement interface, are characterized by a single contribution coefficient, C. Predictions are compared with the results of experimental two-body (pin-on-drum) abrasive wear tests performed on a model aluminum particulate-reinforced epoxy-matrix composite material. In addition, the effects of post heat-treatment on the wear behavior of toughened silicon carbide (ABC-SiC) are investigated by characterizing the role of the microstructures introduced during the post annealing processes. When the annealing temperature is above 1300°C, an aluminum rich secondary phase (nano-precipitate) forms and grows inside the SiC grains. This toughened silicon carbide (ABC-SiC), annealed at temperatures ranging from 0 to 1600°C, is subjected to two- and three-body abrasions with different sizes of abrasives (3˜70 mum). The test results exhibit that the effect of nano-precipitates on wear resistance of post-annealed ABC-SiC is restricted to the abrasion with fine abrasives (3 mum), since nano-precipitates, in the range from 4 nm at 1300°C to 25 nm at 1600°C, are comparable in dimension

  19. Advanced materials for next generation NiMH portable, HEV and EV batteries

    SciTech Connect

    Ovshinsky, S.R.; Dhar, S.K.; Fetcenko, M.A.; Corrigan, D.A.; Reichman, B.; Young, K.; Fierro, C.; Venkatesan, S.; Gifford, P.; Koch, J.

    1998-07-01

    While Ovonic NiMH batteries are already in high volume commercial production for portable applications, advances in materials technology have enabled performance improvements in specific energy (100 Wh/kg), specific power (600-1000 W/kg), high temperature operation, charge retention, and voltage stability. Concurrent with technology advances, Ovonic NiMH batteries have established performance and commercial milestones in electric vehicles, hybrid electric vehicles, as well as scooter, motorcycle and bicycle applications. As important as these advances, significant manufacturing cost reductions have also occurred which allow continued growth of NiMH technology. In this paper, advances in performance, applications and cost reduction are discussed with particular emphasis on the improved proprietary metal hydride and nickel hydroxide materials that make such advances possible.

  20. Thermal Characterization of Nanostructures and Advanced Engineered Materials

    NASA Astrophysics Data System (ADS)

    Goyal, Vivek Kumar

    Continuous downscaling of Si complementary metal-oxide semiconductor (CMOS) technology and progress in high-power electronics demand more efficient heat removal techniques to handle the increasing power density and rising temperature of hot spots. For this reason, it is important to investigate thermal properties of materials at nanometer scale and identify materials with the extremely large or extremely low thermal conductivity for applications as heat spreaders or heat insulators in the next generation of integrated circuits. The thin films used in microelectronic and photonic devices need to have high thermal conductivity in order to transfer the dissipated power to heat sinks more effectively. On the other hand, thermoelectric devices call for materials or structures with low thermal conductivity because the performance of thermoelectric devices is determined by the figure of merit Z=S2sigma/K, where S is the Seebeck coefficient, K and sigma are the thermal and electrical conductivity, respectively. Nanostructured superlattices can have drastically reduced thermal conductivity as compared to their bulk counterparts making them promising candidates for high-efficiency thermoelectric materials. Other applications calling for thin films with low thermal conductivity value are high-temperature coatings for engines. Thus, materials with both high thermal conductivity and low thermal conductivity are technologically important. The increasing temperature of the hot spots in state-of-the-art chips stimulates the search for innovative methods for heat removal. One promising approach is to incorporate materials, which have high thermal conductivity into the chip design. Two suitable candidates for such applications are diamond and graphene. Another approach is to integrate the high-efficiency thermoelectric elements for on-spot cooling. In addition, there is strong motivation for improved thermal interface materials (TIMs) for heat transfer from the heat-generating chip

  1. Advanced Materials for Mercury 50 Gas Turbine Combustion System

    SciTech Connect

    Price, Jeffrey

    2008-09-30

    Solar Turbines Incorporated (Solar), under cooperative agreement number DE-FC26-0CH11049, has conducted development activities to improve the durability of the Mercury 50 combustion system to 30,000 hours life and reduced life cycle costs. This project is part of Advanced Materials in the Advanced Industrial Gas Turbines program in DOE's Office of Distributed Energy. The targeted development engine was the Mercury{trademark} 50 gas turbine, which was developed by Solar under the DOE Advanced Turbine Systems program (DOE contract number DE-FC21-95MC31173). As a generator set, the Mercury 50 is used for distributed power and combined heat and power generation and is designed to achieve 38.5% electrical efficiency, reduced cost of electricity, and single digit emissions. The original program goal was 20,000 hours life, however, this goal was increased to be consistent with Solar's standard 30,000 hour time before overhaul for production engines. Through changes to the combustor design to incorporate effusion cooling in the Generation 3 Mercury 50 engine, which resulted in a drop in the combustor wall temperature, the current standard thermal barrier coated liner was predicted to have 18,000 hours life. With the addition of the advanced materials technology being evaluated under this program, the combustor life is predicted to be over 30,000 hours. The ultimate goal of the program was to demonstrate a fully integrated Mercury 50 combustion system, modified with advanced materials technologies, at a host site for a minimum of 4,000 hours. Solar was the Prime Contractor on the program team, which includes participation of other gas turbine manufacturers, various advanced material and coating suppliers, nationally recognized test laboratories, and multiple industrial end-user field demonstration sites. The program focused on a dual path development route to define an optimum mix of technologies for the Mercury 50 and future gas turbine products. For liner and injector

  2. Energy intensity, electricity consumption, and advanced manufacturing-technology usage

    SciTech Connect

    Doms, M.E.; Dunne, T.

    1995-07-01

    This article reports on the relationship between the usage of advanced manufacturing technologies (AMTs) and energy consumption patterns in manufacturing plants. Using data from the Survey of Manufacturing Technology and the 1987 Census of Manufactures, we model the energy intensity and the electricity intensity of plants as functions of AMT usage and plant age. The main findings are that plants that utilize AMTs are less-energy intensive than plants not using AMTs, but consume proportionately more electricity as a fuel source. Additionally, older plants are generally more energy intensive and rely on fossil fuels to a greater extent than younger plants. 25 refs., 3 tabs.

  3. Advanced materials for high-temperature solid electrolyte applications

    SciTech Connect

    Bates, J.L.; Chick, L.A.; Weber, W.J.; Youngblood, G.E.

    1990-05-01

    Advanced materials for use as electrodes, interconnections, and electrolytes in high-temperature electrochemical applications are under investigation. The air sinterability of La{sub 1-x}Sr{sub x}CrO{sub 3} is highly dependent upon a synergistic relationship between the (La + Sr)/Cr ratio, cation volatility, and second phase formation and transformation. Electrical conductivity in the ZrO{sub 2}--Y{sub 2}O{sub 3}--CeO{sub 2} and ZrO{sub 2}--Y{sub 2}O{sub 3}--TiO{sub 2} systems is highly dependent on composition and atmosphere. The electrochemical processes that occur at the solid-solid-gas interfaces in La(Sr)MnO{sub 3}/ZrO{sub 2}(Y{sub 2}O{sub 3}) have been studied using an unbonded interface cell and impedance spectroscopy. 6 refs., 7 figs.

  4. Advanced High-Temperature Engine Materials Technology Progresses

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The objective of the Advanced High Temperature Engine Materials Technology Program (HITEMP) at the NASA Lewis Research Center is to generate technology for advanced materials and structural analysis that will increase fuel economy, improve reliability, extend life, and reduce operating costs for 21st century civil propulsion systems. The primary focus is on fan and compressor materials (polymer-matrix composites - PMC's), compressor and turbine materials (superalloys, and metal-matrix and intermetallic-matrix composites - MMC's and IMC's), and turbine materials (ceramic-matrix composites - CMC's). These advanced materials are being developed in-house by Lewis researchers and on grants and contracts.

  5. Study of advanced electric propulsion system concept using a flywheel for electric vehicles

    NASA Technical Reports Server (NTRS)

    Younger, F. C.; Lackner, H.

    1979-01-01

    Advanced electric propulsion system concepts with flywheels for electric vehicles are evaluated and it is predicted that advanced systems can provide considerable performance improvement over existing electric propulsion systems with little or no cost penalty. Using components specifically designed for an integrated electric propulsion system avoids the compromises that frequently lead to a loss of efficiency and to inefficient utilization of space and weight. A propulsion system using a flywheel power energy storage device can provide excellent acceleration under adverse conditions of battery degradation due either to very low temperatures or high degrees of discharge. Both electrical and mechanical means of transfer of energy to and from the flywheel appear attractive; however, development work is required to establish the safe limits of speed and energy storage for advanced flywheel designs and to achieve the optimum efficiency of energy transfer. Brushless traction motor designs using either electronic commutation schemes or dc-to-ac inverters appear to provide a practical approach to a mass producible motor, with excellent efficiency and light weight. No comparisons were made with advanced system concepts which do not incorporate a flywheel.

  6. Studies of noise transmission in advanced composite material structures

    NASA Technical Reports Server (NTRS)

    Roussos, L. A.; Mcgary, M. C.; Powell, C. A.

    1983-01-01

    Noise characteristics of advanced composite material fuselages were discussed from the standpoints of applicable research programs and noise transmission theory. Experimental verification of the theory was also included.

  7. Applications of advanced electric/electronic technology to conventional aircraft

    NASA Technical Reports Server (NTRS)

    Heimbold, R. L.

    1980-01-01

    The desirability of seven advanced technologies as applied to three commercial aircraft of 1985 to 1995 was investigated. Digital fly by wire, multiplexing, ring laser gyro, integrated avionics, all electric airplane, electric load management, and fiber optics were considered for 500 passenger, 50 passenger, and 30 passenger aircraft. The major figure of merit used was Net Value of Technology based on procurement and operating cost over the life of the aircraft. An existing computer program, ASSET, was used to resize the aircraft and evalute fuel usage and maintenance costs for each candidate configuration. Conclusions were that, for the 500 passenger aircraft, all candidates had a worthwhile payoff with the all electric airplane having a large payoff.

  8. Nanocrystalline materials: recent advances in crystallographic characterization techniques

    PubMed Central

    Ringe, Emilie

    2014-01-01

    Most properties of nanocrystalline materials are shape-dependent, providing their exquisite tunability in optical, mechanical, electronic and catalytic properties. An example of the former is localized surface plasmon resonance (LSPR), the coherent oscillation of conduction electrons in metals that can be excited by the electric field of light; this resonance frequency is highly dependent on both the size and shape of a nanocrystal. An example of the latter is the marked difference in catalytic activity observed for different Pd nanoparticles. Such examples highlight the importance of particle shape in nanocrystalline materials and their practical applications. However, one may ask ‘how are nanoshapes created?’, ‘how does the shape relate to the atomic packing and crystallography of the material?’, ‘how can we control and characterize the external shape and crystal structure of such small nanocrystals?’. This feature article aims to give the reader an overview of important techniques, concepts and recent advances related to these questions. Nucleation, growth and how seed crystallography influences the final synthesis product are discussed, followed by shape prediction models based on seed crystallography and thermodynamic or kinetic parameters. The crystallographic implications of epitaxy and orientation in multilayered, core-shell nanoparticles are overviewed, and, finally, the development and implications of novel, spatially resolved analysis tools are discussed. PMID:25485133

  9. Novel materials for advanced supercapacitors and Li-ion batteries

    NASA Astrophysics Data System (ADS)

    Yushin, Gleb

    2009-11-01

    High power energy storage devices, such as supercapacitors and Li-ion batteries, are critical for the development of zero-emission electrical vehicles, large scale smart grid, and energy efficient cargo ships and locomotives. The energy storage characteristics of supercapacitors and Li-ion batteries are mostly determined by the specific capacities of their electrodes, while their power characteristics are influenced by the maximum rate of the ion transport. The talk will focus on the development of nanocomposite electrodes capable to improve both the energy and power storage characteristics of the state of the art devices. Advanced ultra-high surface area carbons, carbon-polymer, and carbon-metal oxide nanocomposites have been demonstrated to greatly exceed the specific capacitance of traditional electrodes for supercapacitors. In addition, selected materials showed the unprecedented ultra-fast charging and discharging characteristics. Intelligently designed Si-C composites showed up to 5 times higher specific capacity than graphite, the conventional anode material in Li-ion batteries. Achieving stable performance of Si anodes is commonly a challenge. Recent experiments suggest that individual Si nanoparticles and thin films below a critical size do not fracture and exhibit high reversible capacity for Li. The often observed rapid degradation of Si-based anodes is related not to the intrinsic property of Si but to the loss of electrical contact within the anodes caused by the large volume changes that takes place during Li insertion and extraction. Successful synthesis of high capacity nanocomposite Si-C particles that do not exhibit volume changes during Li insertion and extraction allowed us to achieve stable performance. In order to overcome the limitations of traditional composites precise control over the materials' structure and porosity at the nanoscale was required.

  10. Fabrication and application of advanced functional materials from lignincellulosic biomass

    NASA Astrophysics Data System (ADS)

    Hu, Sixiao

    This dissertation explored the conversion of lignocellulosic biomass into advanced functional materials and their potential applications. Lignocellulosic biomass represents an as-of-yet underutilized renewable source for not only biofuel production but also functional materials fabrication. This renewable source is a great alternative for fossil fuel based chemicals, which could be one of the solutions to energy crisis. In this work, it was demonstrated a variety of advanced materials including functional carbons, metal and silica nanoparticles could be derived from lignocellulosic biomass. Chapter 1 provided overall reviewed of the lignin structures, productions and its utilizations as plastics, absorbents and carbons, as well as the preparation of nano-structured silver, silica and silicon carbide/nitride from biomass. Chapter 2, 3 and 4 discussed the fabrication of highly porous carbons from isolated lignin, and their applications as electric supercapacitors for energy storage. In chapter 2, ultrafine porous carbon fibers were prepared via electrospinning followed by simultaneous carbonization and activation. Chapter 3 covered the fabrication of supercapacitor based on the porous carbon fibers and the investigation of their electrochemical performances. In chapter 4, porous carbon particulates with layered carbon nano plates structures were produced by simple oven-drying followed by simultaneous carbonization and activation. The effects of heat processing parameters on the resulting carbon structures and their electrochemical properties were discussed in details. Chapter 5 and 6 addressed the preparation of silver nanoparticles using lignin. Chapter 5 reported the synthesis, underlying kinetics and mechanism of monodispersed silver nanospheres with diameter less than 25 nm in aqueous solutions using lignin as dual reducing and capping agents. Chapter 6 covered the preparation of silver nanoparticles on electrospun celluloses ultrafine fibers using lignin as both

  11. Advanced Electric Propulsion for RLV Launched Geosynchronous Spacecraft

    NASA Technical Reports Server (NTRS)

    Oleson, Steven

    1999-01-01

    Solar Electric Propulsion (SEP) when used for station keeping and final orbit insertion has been shown to increase a geostationary satellite's payload when launched by existing expendable launch vehicles. In the case of reusable launch vehicles or expendable launch vehicles where an upper stage is an expensive option, this methodology can be modified by using the existing on-board apogee chemical system to perform a perigee burn and then letting the electric propulsion system complete the transfer to geostationary orbit. The elimination of upper stages using on-board chemical and electric propulsion systems was thus examined for GEO spacecraft. Launch vehicle step-down from an Atlas IIAR to a Delta 7920 (no upper stage) was achieved using expanded on-board chemical tanks, 40 kW payload power for electric propulsion, and a 60 day elliptical to GEO SEP orbit insertion. Optimal combined chemical and electric trajectories were found using SEPSPOT. While Hall and ion thrusters provided launch vehicle step-down and even more payload for longer insertion times, NH3 arcjets had insufficient performance to allow launch vehicle step-down. Degradation levels were only 5% to 7% for launch step-down cases using advanced solar arrays. Results were parameterized to allow comparisons for future reusable launch vehicles. Results showed that for an 8 W/kg initial power/launch mass power density spacecraft, 50% to 100% more payload can be launched using this method.

  12. Analysis of an advanced technology subsonic turbofan incorporating revolutionary materials

    NASA Technical Reports Server (NTRS)

    Knip, Gerald, Jr.

    1987-01-01

    Successful implementation of revolutionary composite materials in an advanced turbofan offers the possibility of further improvements in engine performance and thrust-to-weight ratio relative to current metallic materials. The present analysis determines the approximate engine cycle and configuration for an early 21st century subsonic turbofan incorporating all composite materials. The advanced engine is evaluated relative to a current technology baseline engine in terms of its potential fuel savings for an intercontinental quadjet having a design range of 5500 nmi and a payload of 500 passengers. The resultant near optimum, uncooled, two-spool, advanced engine has an overall pressure ratio of 87, a bypass ratio of 18, a geared fan, and a turbine rotor inlet temperature of 3085 R. Improvements result in a 33-percent fuel saving for the specified misssion. Various advanced composite materials are used throughout the engine. For example, advanced polymer composite materials are used for the fan and the low pressure compressor (LPC).

  13. Advanced Electric Propulsion for Space Solar Power Satellites

    NASA Technical Reports Server (NTRS)

    Oleson, Steve

    1999-01-01

    The sun tower concept of collecting solar energy in space and beaming it down for commercial use will require very affordable in-space as well as earth-to-orbit transportation. Advanced electric propulsion using a 200 kW power and propulsion system added to the sun tower nodes can provide a factor of two reduction in the required number of launch vehicles when compared to in-space cryogenic chemical systems. In addition, the total time required to launch and deliver the complete sun tower system is of the same order of magnitude using high power electric propulsion or cryogenic chemical propulsion: around one year. Advanced electric propulsion can also be used to minimize the stationkeeping propulsion system mass for this unique space platform. 50 to 100 kW class Hall, ion, magnetoplasmadynamic, and pulsed inductive thrusters are compared. High power Hall thruster technology provides the best mix of launches saved and shortest ground to Geosynchronous Earth Orbital Environment (GEO) delivery time of all the systems, including chemical. More detailed studies comparing launch vehicle costs, transfer operations costs, and propulsion system costs and complexities must be made to down-select a technology. The concept of adding electric propulsion to the sun tower nodes was compared to a concept using re-useable electric propulsion tugs for Low Earth Orbital Environment (LEO) to GEO transfer. While the tug concept would reduce the total number of required propulsion systems, more launchers and notably longer LEO to GEO and complete sun tower ground to GEO times would be required. The tugs would also need more complex, longer life propulsion systems and the ability to dock with sun tower nodes.

  14. Advances in design and modeling of porous materials

    NASA Astrophysics Data System (ADS)

    Ayral, André; Calas-Etienne, Sylvie; Coasne, Benoit; Deratani, André; Evstratov, Alexis; Galarneau, Anne; Grande, Daniel; Hureau, Matthieu; Jobic, Hervé; Morlay, Catherine; Parmentier, Julien; Prelot, Bénédicte; Rossignol, Sylvie; Simon-Masseron, Angélique; Thibault-Starzyk, Frédéric

    2015-07-01

    This special issue of the European Physical Journal Special Topics is dedicated to selected papers from the symposium "High surface area porous and granular materials" organized in the frame of the conference "Matériaux 2014", held on November 24-28, 2014 in Montpellier, France. Porous materials and granular materials gather a wide variety of heterogeneous, isotropic or anisotropic media made of inorganic, organic or hybrid solid skeletons, with open or closed porosity, and pore sizes ranging from the centimeter scale to the sub-nanometer scale. Their technological and industrial applications cover numerous areas from building and civil engineering to microelectronics, including also metallurgy, chemistry, health, waste water and gas effluent treatment. Many emerging processes related to environmental protection and sustainable development also rely on this class of materials. Their functional properties are related to specific transfer mechanisms (matter, heat, radiation, electrical charge), to pore surface chemistry (exchange, adsorption, heterogeneous catalysis) and to retention inside confined volumes (storage, separation, exchange, controlled release). The development of innovative synthesis, shaping, characterization and modeling approaches enables the design of advanced materials with enhanced functional performance. The papers collected in this special issue offer a good overview of the state-of-the-art and science of these complex media. We would like to thank all the speakers and participants for their contribution to the success of the symposium. We also express our gratitude to the organization committee of "Matériaux 2014". We finally thank the reviewers and the staff of the European Physical Journal Special Topics who made the publication of this special issue possible.

  15. An Advanced Decision Support Tool for Electricity Infrastructure Operations

    SciTech Connect

    Chen, Yousu; Huang, Zhenyu; Wong, Pak C.; Mackey, Patrick S.; Allwardt, Craig H.; Ma, Jian; Greitzer, Frank L.

    2010-01-31

    Electricity infrastructure, as one of the most critical infrastructures in the U.S., plays an important role in modern societies. Its failure would lead to significant disruption of people’s lives, industry and commercial activities, and result in massive economic losses. Reliable operation of electricity infrastructure is an extremely challenging task because human operators need to consider thousands of possible configurations in near real-time to choose the best option and operate the network effectively. In today’s practice, electricity infrastructure operation is largely based on operators’ experience with very limited real-time decision support, resulting in inadequate management of complex predictions and the inability to anticipate, recognize, and respond to situations caused by human errors, natural disasters, or cyber attacks. Therefore, a systematic approach is needed to manage the complex operational paradigms and choose the best option in a near-real-time manner. This paper proposes an advanced decision support tool for electricity infrastructure operations. The tool has the functions of turning large amount of data into actionable information to help operators monitor power grid status in real time; performing trend analysis to indentify system trend at the regional level or system level to help the operator to foresee and discern emergencies, studying clustering analysis to assist operators to identify the relationships between system configurations and affected assets, and interactively evaluating the alternative remedial actions to aid operators to make effective and timely decisions. This tool can provide significant decision support on electricity infrastructure operations and lead to better reliability in power grids. This paper presents examples with actual electricity infrastructure data to demonstrate the capability of this tool.

  16. Advanced materials for space nuclear power systems

    NASA Technical Reports Server (NTRS)

    Titran, Robert H.; Grobstein, Toni L.; Ellis, David L.

    1991-01-01

    The overall philosophy of the research was to develop and characterize new high temperature power conversion and radiator materials and to provide spacecraft designers with material selection options and design information. Research on three candidate materials (carbide strengthened niobium alloy PWC-11 for fuel cladding, graphite fiber reinforced copper matrix composites for heat rejection fins, and tungsten fiber reinforced niobium matrix composites for fuel containment and structural supports) considered for space power system applications is discussed. Each of these types of materials offers unique advantages for space power applications.

  17. Advanced materials for space nuclear power systems

    NASA Technical Reports Server (NTRS)

    Titran, Robert H.; Grobstein, Toni L.; Ellis, David L.

    1991-01-01

    The overall philosophy of the research was to develop and characterize new high temperature power conversion and radiator materials and to provide spacecraft designers with material selection options and design information. Research on three candidate materials (carbide strengthened niobium alloy PWC-11 for fuel cladding, graphite fiber reinforced copper matrix composites for heat rejection fins, and tungsten fiber reinforced niobium matrix composites for fuel containment and structural supports considered for space power system applications is discussed. Each of these types of materials offers unique advantages for space power applications.

  18. Hybrid and electric advanced vehicle systems (heavy) simulation

    NASA Technical Reports Server (NTRS)

    Hammond, R. A.; Mcgehee, R. K.

    1981-01-01

    A computer program to simulate hybrid and electric advanced vehicle systems (HEAVY) is described. It is intended for use early in the design process: concept evaluation, alternative comparison, preliminary design, control and management strategy development, component sizing, and sensitivity studies. It allows the designer to quickly, conveniently, and economically predict the performance of a proposed drive train. The user defines the system to be simulated using a library of predefined component models that may be connected to represent a wide variety of propulsion systems. The development of three models are discussed as examples.

  19. Progress in advanced high temperature materials technology

    NASA Technical Reports Server (NTRS)

    Freche, J. C.; Ault, G. M.

    1976-01-01

    Significant progress has recently been made in many high temperature material categories pertinent to such applications by the industrial community. These include metal matrix composites, superalloys, directionally solidified eutectics, coatings, and ceramics. Each of these material categories is reviewed and the current state-of-the-art identified, including some assessment, when appropriate, of progress, problems, and future directions.

  20. Electrochemical cell with powdered electrically insulative material as a separator

    DOEpatents

    Mathers, James P.; Olszanski, Theodore W.; Boquist, Carl W.

    1978-01-01

    A secondary electrochemical cell includes electrodes separated by a layer of electrically insulative powder. The powder includes refractory materials selected from the oxides and nitrides of metals and metaloids. The powdered refractory material, blended with electrolyte particles, can be compacted in layers with electrode materials to form an integral electrode structure or separately assembled into the cell. The assembled cell is heated to operating temperature leaving porous layers of electrically insulative, refractory particles, containing molten electrolyte between the electrodes.

  1. Electric vehicle traction motors - The development of an advanced motor concept

    NASA Technical Reports Server (NTRS)

    Campbell, P.

    1980-01-01

    An axial-field permanent magnet traction motor is described, similar to several advanced motors that are being developed in the United States. This type of machine has several advantages over conventional dc motors, particularly in the electric vehicle application. The rapidly changing cost of magnetic materials, particularly cobalt, makes it important to study the utilization of permanent magnet materials in such machines. The impact of different magnets on machine design is evaluated, and the advantages of using iron powder composites in the armature are assessed.

  2. Challenge to advanced materials processing with lasers in Japan

    NASA Astrophysics Data System (ADS)

    Miyamoto, Isamu

    2003-02-01

    Japan is one of the most advanced countries in manufacturing technology, and lasers have been playing an important role for advancement of manufacturing technology in a variety of industrial fields. Contribution of laser materials processing to Japanese industry is significant for both macroprocessing and microprocessing. The present paper describes recent trend and topics of industrial applications in terms of the hardware and the software to show how Japanese industry challenges to advanced materials processing using lasers, and national products related to laser materials processing are also briefly introduced.

  3. Advanced Materials and Cell Components for NASA's Exploration Missions

    NASA Technical Reports Server (NTRS)

    Reid, Concha M.

    2009-01-01

    This is an introductory paper for the focused session "Advanced Materials and Cell Components for NASA's Exploration Missions". This session will concentrate on electrochemical advances in materials and components that have been achieved through efforts sponsored under NASA's Exploration Systems Mission Directorate (ESMD). This paper will discuss the performance goals for components and for High Energy and Ultra High Energy cells, advanced lithium-ion cells that will offer a combination of higher specific energy and improved safety over state-of-the-art. Papers in this session will span a broad range of materials and components that are under development to enable these cell development efforts.

  4. Advanced lubrication systems and materials. Final report

    SciTech Connect

    Hsu, S.

    1998-05-07

    This report described the work conducted at the National Institute of Standards and Technology under an interagency agreement signed in September 1992 between DOE and NIST for 5 years. The interagency agreement envisions continual funding from DOE to support the development of fuel efficient, low emission engine technologies in terms of lubrication, friction, and wear control encountered in the development of advanced transportation technologies. However, in 1994, the DOE office of transportation technologies was reorganized and the tribology program was dissolved. The work at NIST therefore continued at a low level without further funding from DOE. The work continued to support transportation technologies in the development of fuel efficient, low emission engine development. Under this program, significant progress has been made in advancing the state of the art of lubrication technology for advanced engine research and development. Some of the highlights are: (1) developed an advanced high temperature liquid lubricant capable of sustaining high temperatures in a prototype heat engine; (2) developed a novel liquid lubricant which potentially could lower the emission of heavy duty diesel engines; (3) developed lubricant chemistries for ceramics used in the heat engines; (4) developed application maps for ceramic lubricant chemistry combinations for design purpose; and (5) developed novel test methods to screen lubricant chemistries for automotive air-conditioning compressors lubricated by R-134a (Freon substitute). Most of these findings have been reported to the DOE program office through Argonne National Laboratory who manages the overall program. A list of those reports and a copy of the report submitted to the Argonne National Laboratory is attached in Appendix A. Additional reports have also been submitted separately to DOE program managers. These are attached in Appendix B.

  5. Advances in Processing of Bulk Ferroelectric Materials

    NASA Astrophysics Data System (ADS)

    Galassi, Carmen

    The development of ferroelectric bulk materials is still under extensive investigation, as new and challenging issues are growing in relation to their widespread applications. Progress in understanding the fundamental aspects requires adequate technological tools. This would enable controlling and tuning the material properties as well as fully exploiting them into the scale production. Apart from the growing number of new compositions, interest in the first ferroelectrics like BaTiO3 or PZT materials is far from dropping. The need to find new lead-free materials, with as high performance as PZT ceramics, is pushing towards a full exploitation of bariumbased compositions. However, lead-based materials remain the best performing at reasonably low production costs. Therefore, the main trends are towards nano-size effects and miniaturisation, multifunctional materials, integration, and enhancement of the processing ability in powder synthesis. Also, in control of dispersion and packing, to let densification occur in milder conditions. In this chapter, after a general review of the composition and main properties of the principal ferroelectric materials, methods of synthesis are analysed with emphasis on recent results from chemical routes and cold consolidation methods based on the colloidal processing.

  6. Advanced materials for radiation-cooled rockets

    NASA Astrophysics Data System (ADS)

    Reed, Brian; Biaglow, James; Schneider, Steven

    1993-11-01

    The most common material system currently used for low thrust, radiation-cooled rockets is a niobium alloy (C-103) with a fused silica coating (R-512A or R-512E) for oxidation protection. However, significant amounts of fuel film cooling are usually required to keep the material below its maximum operating temperature of 1370 C, degrading engine performance. Also the R-512 coating is subject to cracking and eventual spalling after repeated thermal cycling. A new class of high-temperature, oxidation-resistant materials are being developed for radiation-cooled rockets, with the thermal margin to reduce or eliminate fuel film cooling, while still exceeding the life of silicide-coated niobium. Rhenium coated with iridium is the most developed of these high-temperature materials. Efforts are on-going to develop 22 N, 62 N, and 440 N engines composed of these materials for apogee insertion, attitude control, and other functions. There is also a complimentary NASA and industry effort to determine the life limiting mechanisms and characterize the thermomechanical properties of these materials. Other material systems are also being studied which may offer more thermal margin and/or oxidation resistance, such as hafnium carbide/tantalum carbide matrix composites and ceramic oxide-coated iridium/rhenium chambers.

  7. Advanced materials for radiation-cooled rockets

    NASA Technical Reports Server (NTRS)

    Reed, Brian; Biaglow, James; Schneider, Steven

    1993-01-01

    The most common material system currently used for low thrust, radiation-cooled rockets is a niobium alloy (C-103) with a fused silica coating (R-512A or R-512E) for oxidation protection. However, significant amounts of fuel film cooling are usually required to keep the material below its maximum operating temperature of 1370 C, degrading engine performance. Also the R-512 coating is subject to cracking and eventual spalling after repeated thermal cycling. A new class of high-temperature, oxidation-resistant materials are being developed for radiation-cooled rockets, with the thermal margin to reduce or eliminate fuel film cooling, while still exceeding the life of silicide-coated niobium. Rhenium coated with iridium is the most developed of these high-temperature materials. Efforts are on-going to develop 22 N, 62 N, and 440 N engines composed of these materials for apogee insertion, attitude control, and other functions. There is also a complimentary NASA and industry effort to determine the life limiting mechanisms and characterize the thermomechanical properties of these materials. Other material systems are also being studied which may offer more thermal margin and/or oxidation resistance, such as hafnium carbide/tantalum carbide matrix composites and ceramic oxide-coated iridium/rhenium chambers.

  8. Barriers to applying advanced high-temperature materials

    NASA Astrophysics Data System (ADS)

    Premkumar, M. K.

    1993-01-01

    During the past 25 years, aerospace engineers and material scientists have made significant technical progress toward developing next-generation aircraft. However, while advanced high-temperature materials continue to be developed, the outlook for their future application is uncertain and will depend on the ability of these materials to satisfy a more diverse market.

  9. Advanced materials research for long-haul aircraft turbine engines

    NASA Technical Reports Server (NTRS)

    Signorelli, R. A.; Blankenship, C. P.

    1978-01-01

    The status of research efforts to apply low to intermediate temperature composite materials and advanced high temperature materials to engine components is reviewed. Emerging materials technologies and their potential benefits to aircraft gas turbines were emphasized. The problems were identified, and the general state of the technology for near term use was assessed.

  10. Lignin-Derived Advanced Carbon Materials

    SciTech Connect

    Chatterjee, Sabornie; Saito, Tomonori

    2015-01-01

    Lignin is a highly abundant source of renewable carbon that can be considered as a valuable sustainable source of biobased materials. By application specific pretreatments and manufacturing method, lignin can be converted to a variety of value added carbon materials. However, the physical and chemical heterogenitites in lignin complicate its use as a feedstock. In this review, lignin manufacturing process, effects of pretreatments and manufacturing methods on the properties of lignin, properties and applications of various lignin derived carbon materials such as carbon fibers, carbon mats, activated carbons, carbon films; are discussed.

  11. Advances in nonlinear optical materials and devices

    NASA Technical Reports Server (NTRS)

    Byer, Robert L.

    1991-01-01

    The recent progress in the application of nonlinear techniques to extend the frequency of laser sources has come from the joint progress in laser sources and in nonlinear materials. A brief summary of the progress in diode pumped solid state lasers is followed by an overview of progress in nonlinear frequency extension by harmonic generation and parametric processes. Improved nonlinear materials including bulk crystals, quasiphasematched interactions, guided wave devices, and quantum well intersubband studies are discussed with the idea of identifying areas of future progress in nonlinear materials and devices.

  12. Lignin-Derived Advanced Carbon Materials.

    PubMed

    Chatterjee, Sabornie; Saito, Tomonori

    2015-12-01

    Lignin is a highly abundant source of renewable carbon that can be considered as a valuable sustainable source of biobased materials. By applying specific pretreatments and manufacturing methods, lignin can be converted into a variety of value-added carbon materials. However, the physical and chemical heterogeneities of lignin complicate its use as a feedstock. Herein lignin manufacturing process, the effects of pretreatments and manufacturing methods on the properties of product lignin, and structure-property relationships in various applications of lignin-derived carbon materials, such as carbon fibers, carbon mats, activated carbons, carbon films, and templated carbon, are discussed. PMID:26568373

  13. Lignin-Derived Advanced Carbon Materials

    SciTech Connect

    Chatterjee, Sabornie; Saito, Tomonori

    2015-11-16

    Lignin is a highly abundant source of renewable carbon that can be considered as a valuable sustainable source of biobased materials. By applying specific pretreatments and manufacturing methods, it has been found that lignin can be converted into a variety of value-added carbon materials. However, the physical and chemical heterogeneities of lignin complicate its use as a feedstock. Herein, we discuss the lignin manufacturing process, the effects of pretreatments and manufacturing methods on the properties of product lignin, and structure–property relationships in various applications of lignin-derived carbon materials, such as carbon fibers, carbon mats, activated carbons, carbon films, and templated carbon.

  14. Nanomaterials for Polymer Electrolyte Membrane Fuel Cells; Materials Challenges Facing Electrical Energy Storate

    SciTech Connect

    Gopal Rao, MRS Web-Editor; Yury Gogotsi, Drexel University; Karen Swider-Lyons, Naval Research Laboratory

    2010-08-05

    Symposium T: Nanomaterials for Polymer Electrolyte Membrane Fuel Cells Polymer electrolyte membrane (PEM) fuel cells are under intense investigation worldwide for applications ranging from transportation to portable power. The purpose of this seminar is to focus on the nanomaterials and nanostructures inherent to polymer fuel cells. Symposium topics will range from high-activity cathode and anode catalysts, to theory and new analytical methods. Symposium U: Materials Challenges Facing Electrical Energy Storage Electricity, which can be generated in a variety of ways, offers a great potential for meeting future energy demands as a clean and efficient energy source. However, the use of electricity generated from renewable sources, such as wind or sunlight, requires efficient electrical energy storage. This symposium will cover the latest material developments for batteries, advanced capacitors, and related technologies, with a focus on new or emerging materials science challenges.

  15. Advanced diffusion studies with isotopically controlled materials

    SciTech Connect

    Bracht, Hartmut A.; Silvestri, Hughes H.; Haller, Eugene E.

    2004-11-14

    The use of enriched stable isotopes combined with modern epitaxial deposition and depth profiling techniques enables the preparation of material heterostructures, highly appropriate for self- and foreign-atom diffusion experiments. Over the past decade we have performed diffusion studies with isotopically enriched elemental and compound semiconductors. In the present paper we highlight our recent results and demonstrate that the use of isotopically enriched materials ushered in a new era in the study of diffusion in solids which yields greater insight into the properties of native defects and their roles in diffusion. Our approach of studying atomic diffusion is not limited to semiconductors and can be applied also to other material systems. Current areas of our research concern the diffusion in the silicon-germanium alloys and glassy materials such as silicon dioxide and ion conducting silicate glasses.

  16. Marine applications for advanced composite materials

    SciTech Connect

    Hihara, L.H.; Bregman, R.; Takahashi, P.K.

    1993-12-31

    Very large floating structures (VLFSs) may one day be essential to the study and utilization of the ocean. Some possible applications for VLFSs are ocean ranching homeports. observatories for ocean research, seabed mineral refineries, energy generation platforms. and waste management facilities. A VLFS that is in the conceptual phase, and may one day be based off the coast of Hawaii, has been named Blue Revolution. Candidate materials for Blue Revolution were identified based on criteria of rigidity, strength, and weight. Priority was given to materials that could be used to construct lightweight VLFSs. Major static forces were considered in this preliminary analysis. The best materials were identified as those having low values of density/modulus ({rho}/E) and density/strength ({rho}/{sigma}). Concrete, metal alloys, organic-matrix composites (OMCs), and metal-matrix composites (MMCs) were evaluated. OMCs and MMCs were generally the best materials based on their very low {rho}/E and {rho}/{sigma} values.

  17. Electrical properties of commercial sheet insulation materials for cryogenic applications

    SciTech Connect

    Tuncer, Enis; Sauers, Isidor; James, David Randy; Ellis, Alvin R; Pace, Marshall O

    2008-01-01

    Dielectric properties of electrical insulation materials are needed for low-temperature power applications. Performance of materials and their compatibility determine the size of the electrical insulation in power equipment. In this work we report the dielectric properties of some commercially available materials in sheet form. The selected materials are polypropylene laminated paper from Sumitomo Electric U.S.A., Inc., porous polyethylene (Tyvek\\texttrademark) from Dupont, and polyamide paper (Nomex\\texttrademark) from Dupont. The dielectric properties are characterized with an electrical impedance analyzer in the frequency domain. The impedances are recorded in a cryocooler in the temperature range from 50 to 300 K. The dielectric breakdown characteristics of the materials are measured in a liquid nitrogen bath at atmospheric pressure.

  18. Materials of construction for advanced coal conversion systems

    SciTech Connect

    Nangia, V.K.

    1982-01-01

    This book describes materials of construction, and materials problems for equipment used in advanced coal conversion systems. The need for cost effective industrial operation is always a prime concern, particularly in this age of energy consciousness. Industry is continually seeking improved materials for more efficient systems. The information presented here is intended to be of use in the design and planning of these systems. Coal conversion and utilization impose severe demands on construction materials because of high temperature, high pressure, corrosive/erosive, and other hostile environmental factors. Successful economic development of these processes can be achieved only to the extent that working materials can withstand increasingly more aggressive operating conditions. The book, which reviews present and past work on the behavior of materials in the environments of advanced coal conversion systems, is divided into three parts: atmospheric fluidized bed combustion, coal gasification and liquefaction, and advanced power systems.

  19. Rubber-like electrically conductive polymeric materials with shape memory

    NASA Astrophysics Data System (ADS)

    Cui, H. P.; Song, C. L.; Huang, W. M.; Wang, C. C.; Zhao, Y.

    2013-05-01

    This paper presents a heating-responsive shape memory polymeric material, which is not only rubber-like at room temperature and above its shape recovery temperature, but also electrically conductive. This polymeric material is made of silicone, melting glue (MG), and carbon black (CB). The influence of volume fractions of MG and CB on the elasticity, electrical resistivity, and shape memory effect of the polymeric material is systematically investigated. The feasibility of Joule heating for shape recovery is experimentally demonstrated with an electric power of 31 V.

  20. Advanced Materials and Solids Analysis Research Core (AMSARC)

    EPA Science Inventory

    The Advanced Materials and Solids Analysis Research Core (AMSARC), centered at the U.S. Environmental Protection Agency's (EPA) Andrew W. Breidenbach Environmental Research Center in Cincinnati, Ohio, is the foundation for the Agency's solids and surfaces analysis capabilities. ...

  1. Advanced organic composite materials for aircraft structures: Future program

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Revolutionary advances in structural materials have been responsible for revolutionary changes in all fields of engineering. These advances have had and are still having a significant impact on aircraft design and performance. Composites are engineered materials. Their properties are tailored through the use of a mix or blend of different constituents to maximize selected properties of strength and/or stiffness at reduced weights. More than 20 years have passed since the potentials of filamentary composite materials were identified. During the 1970s much lower cost carbon filaments became a reality and gradually designers turned from boron to carbon composites. Despite progress in this field, filamentary composites still have significant unfulfilled potential for increasing aircraft productivity; the rendering of advanced organic composite materials into production aircraft structures was disappointingly slow. Why this is and research and technology development actions that will assist in accelerating the application of advanced organic composites to production aircraft is discussed.

  2. Advanced Engineering Materials: Products from Super Stuff. Resources in Technology.

    ERIC Educational Resources Information Center

    Jacobs, James A.

    1993-01-01

    Discusses the development of "smart" or advanced materials such as ceramics, metals, composites, and polymers. Provides a design brief, a student learning activity with outcomes, quiz, and resources. (SK)

  3. Lignin-Derived Advanced Carbon Materials

    DOE PAGESBeta

    Chatterjee, Sabornie; Saito, Tomonori

    2015-11-16

    Lignin is a highly abundant source of renewable carbon that can be considered as a valuable sustainable source of biobased materials. By applying specific pretreatments and manufacturing methods, it has been found that lignin can be converted into a variety of value-added carbon materials. However, the physical and chemical heterogeneities of lignin complicate its use as a feedstock. Herein, we discuss the lignin manufacturing process, the effects of pretreatments and manufacturing methods on the properties of product lignin, and structure–property relationships in various applications of lignin-derived carbon materials, such as carbon fibers, carbon mats, activated carbons, carbon films, and templatedmore » carbon.« less

  4. Recovery Act - Sustainable Transportation: Advanced Electric Drive Vehicle Education Program

    SciTech Connect

    Caille, Gary

    2013-12-13

    The collective goals of this effort include: 1) reach all facets of this society with education regarding electric vehicles (EV) and plug–in hybrid electric vehicles (PHEV), 2) prepare a workforce to service these advanced vehicles, 3) create web–based learning at an unparalleled level, 4) educate secondary school students to prepare for their future and 5) train the next generation of professional engineers regarding electric vehicles. The Team provided an integrated approach combining secondary schools, community colleges, four–year colleges and community outreach to provide a consistent message (Figure 1). Colorado State University Ventures (CSUV), as the prime contractor, plays a key program management and co–ordination role. CSUV is an affiliate of Colorado State University (CSU) and is a separate 501(c)(3) company. The Team consists of CSUV acting as the prime contractor subcontracted to Arapahoe Community College (ACC), CSU, Motion Reality Inc. (MRI), Georgia Institute of Technology (Georgia Tech) and Ricardo. Collaborators are Douglas County Educational Foundation/School District and Gooru (www.goorulearning.org), a nonprofit web–based learning resource and Google spin–off.

  5. Advanced electric field computation for RF sheaths prediction with TOPICA

    NASA Astrophysics Data System (ADS)

    Milanesio, Daniele; Maggiora, Riccardo

    2012-10-01

    The design of an Ion Cyclotron (IC) launcher is not only driven by its coupling properties, but also by its capability of maintaining low parallel electric fields in front of it, in order to provide good power transfer to plasma and to reduce the impurities production. However, due to the impossibility to verify the antenna performances before the starting of the operations, advanced numerical simulation tools are the only alternative to carry out a proper antenna design. With this in mind, it should be clear that the adoption of a code, such as TOPICA [1], able to precisely take into account a realistic antenna geometry and an accurate plasma description, is extremely important to achieve these goals. Because of the recently introduced features that allow to compute the electric field distribution everywhere inside the antenna enclosure and in the plasma column, the TOPICA code appears to be the only alternative to understand which elements may have a not negligible impact on the antenna design and then to suggest further optimizations in order to mitigate RF potentials. The present work documents the evaluation of the electric field map from actual antennas, like the Tore Supra Q5 and the JET A2 launchers, and the foreseen ITER IC antenna. [4pt] [1] D. Milanesio et al., Nucl. Fusion 49, 115019 (2009).

  6. Results of advanced battery technology evaluations for electric vehicle applications

    SciTech Connect

    DeLuca, W.H.; Gillie, K.R.; Kulaga, J.E.; Smaga, J.A.; Tummillo, A.F.; Webster, C.E.

    1992-09-01

    Advanced battery technology evaluations are performed under simulated electric-vehicle operating conditions at the Analysis & Diagnostic Laboratory (ADL) of Argonne National Laboratory. The ADL results provide insight Into those factors that limit battery performance and life. The ADL facilities include a test laboratory to conduct battery experimental evaluations under simulated application conditions and a post-test analysis laboratory to determine, In a protected atmosphere if needed, component compositional changes and failure mechanisms. This paper summarizes the performance characterizations and life evaluations conducted during 1991--1992 on both single cells and multi-cell modules that encompass eight battery technologies [Na/S, Li/MS (M=metal), Ni/MH, Ni/Cd, Ni/Zn, Ni/Fe, Zn/Br, and Pb-acid]. These evaluations were performed for the Department of Energy, Office of Transportation Technologies, Electric and Hybrid Propulsion Division, and the Electric Power Research Institute. The ADL provides a common basis for battery performance characterization and life evaluations with unbiased application of tests and analyses. The results help identify the most-promising R&D approaches for overcoming battery limitations, and provide battery users, developers, and program managers with a measure of the progress being made in battery R&D programs, a comparison of battery technologies, and basic data for modeling.

  7. Results of advanced batter technology evaluations for electric vehicle applications

    SciTech Connect

    DeLuca, W.H.; Gillie, K.R.; Kulaga, J.E.; Smaga, J.A.; Tummillo, A.F.; Webster, C.E.

    1992-01-01

    Advanced battery technology evaluations are performed under simulated electric-vehicle operating conditions at the Analysis Diagnostic Laboratory (ADL) of Argonne National Laboratory. The ADL results provide insight Into those factors that limit battery performance and life. The ADL facilities include a test laboratory to conduct battery experimental evaluations under simulated application conditions and a post-test analysis laboratory to determine, In a protected atmosphere if needed, component compositional changes and failure mechanisms. This paper summarizes the performance characterizations and life evaluations conducted during 1991--1992 on both single cells and multi-cell modules that encompass eight battery technologies (Na/S, Li/MS (M=metal), Ni/MH, Ni/Cd, Ni/Zn, Ni/Fe, Zn/Br, and Pb-acid). These evaluations were performed for the Department of Energy, Office of Transportation Technologies, Electric and Hybrid Propulsion Division, and the Electric Power Research Institute. The ADL provides a common basis for battery performance characterization and life evaluations with unbiased application of tests and analyses. The results help identify the most-promising R D approaches for overcoming battery limitations, and provide battery users, developers, and program managers with a measure of the progress being made in battery R D programs, a comparison of battery technologies, and basic data for modeling.

  8. Advance Abrasion Resistant Materials for Mining

    SciTech Connect

    Mackiewicz-Ludtka, G.

    2004-06-01

    The high-density infrared (HDI) transient-liquid coating (TLC) process was successfully developed and demonstrated excellent, enhanced (5 times higher than the current material and process) wear performance for the selected functionally graded material (FGM) coatings under laboratory simulated, in-service conditions. The mating steel component exhibited a wear rate improvement of approximately one and a half (1.5) times. After 8000 cycles of. wear testing, the full-scale component testing demonstrated that the coating integrity was still excellent. Little or no spalling was observed to occur.

  9. ADVANCED ABRASION RESISTANT MATERIALS FOR MINING

    SciTech Connect

    Ludtka, G.M.

    2004-04-08

    The high-density infrared (HDI) transient-liquid coating (TLC) process was successfully developed and demonstrated excellent, enhanced (5 times higher than the current material and process) wear performance for the selected functionally graded material (FGM) coatings under laboratory simulated, in-service conditions. The mating steel component exhibited a wear rate improvement of approximately one and a half (1.5) times. After 8000 cycles of wear testing, the full-scale component testing demonstrated that the coating integrity was still excellent. Little or no spalling was observed to occur.

  10. Recycling readiness of advanced batteries for electric vehicles

    SciTech Connect

    Jungst, R.G.

    1997-09-01

    Maximizing the reclamation/recycle of electric-vehicle (EV) batteries is considered to be essential for the successful commercialization of this technology. Since the early 1990s, the US Department of Energy has sponsored the ad hoc advanced battery readiness working group to review this and other possible barriers to the widespread use of EVs, such as battery shipping and in-vehicle safety. Regulation is currently the main force for growth in EV numbers and projections for the states that have zero-emission vehicle (ZEV) programs indicate about 200,000 of these vehicles would be offered to the public in 2003 to meet those requirements. The ad hoc Advanced Battery Readiness Working Group has identified a matrix of battery technologies that could see use in EVs and has been tracking the state of readiness of recycling processes for each of them. Lead-acid, nickel/metal hydride, and lithium-ion are the three EV battery technologies proposed by the major automotive manufacturers affected by ZEV requirements. Recycling approaches for the two advanced battery systems on this list are partly defined, but could be modified to recover more value from end-of-life batteries. The processes being used or planned to treat these batteries are reviewed, as well as those being considered for other longer-term technologies in the battery recycling readiness matrix. Development efforts needed to prepare for recycling the batteries from a much larger EV population than exists today are identified.

  11. Boron Carbides As Thermo-electric Materials

    NASA Technical Reports Server (NTRS)

    Wood, Charles

    1988-01-01

    Report reviews recent theoretical and experimental research on thermoelectric materials. Recent work with narrow-band semiconductors demonstrated possibility of relatively high thermoelectric energy-conversion efficiencies in materials withstanding high temperatures needed to attain such efficiencies. Among promising semiconductors are boron-rich borides, especially boron carbides.

  12. Fabrication of Advanced Thermoelectric Materials by Hierarchical Nanovoid Generation

    NASA Technical Reports Server (NTRS)

    Choi, Sang Hyouk (Inventor); Park, Yeonjoon (Inventor); Chu, Sang-Hyon (Inventor); Elliott, James R. (Inventor); King, Glen C. (Inventor); Kim, Jae-Woo (Inventor); Lillehei, Peter T. (Inventor); Stoakley, Diane M. (Inventor)

    2011-01-01

    A novel method to prepare an advanced thermoelectric material has hierarchical structures embedded with nanometer-sized voids which are key to enhancement of the thermoelectric performance. Solution-based thin film deposition technique enables preparation of stable film of thermoelectric material and void generator (voigen). A subsequent thermal process creates hierarchical nanovoid structure inside the thermoelectric material. Potential application areas of this advanced thermoelectric material with nanovoid structure are commercial applications (electronics cooling), medical and scientific applications (biological analysis device, medical imaging systems), telecommunications, and defense and military applications (night vision equipments).

  13. NIST Materials Properties Databases for Advanced Ceramics

    PubMed Central

    Munro, R. G.

    2001-01-01

    The NIST Ceramics Division maintains two databases on the physical, mechanical, thermal, and other properties of high temperature superconductors and structural ceramics. Crystallographic data are featured prominently among the physical property data and serve several important functions in the classification and evaluation of the property values. The scope of materials, properties, and data evaluation protocols are discussed for the two databases.

  14. Evaluation of advanced materials. Final report

    SciTech Connect

    Wright, I.G.; Clauer, A.H.; Shetty, D.K.; Tucker, T.R.; Stropki, J.T.

    1982-11-18

    Cemented tungsten carbides with a binder level in the range of 5 to 6 percent exhibited the best resistance to erosion for this class of materials. Other practical cermet meterials were diamond - Si/SiC, Al/sub 2/O/sub 3/-B/sub 4/C-Cr, and B/sub 4/C-Co. SiAlON exhibited erosion resistance equivalent to the best WC-cermet. The only coating system to show promise of improved erosion resistance was CVD TiB/sub 2/ on cemented TiB/sub 2/-Ni. Cracking and/or spalling of a TiC coating and a proprietary TMT coating occurred in the standard slurry erosion test. Ranking of cemented tungsten carbide materials in the laboratory erosion test was the same as that found in service in the Wilsonville pilot plant. Specimens from the Fort Lewis pilot plant which performed well in service exhibited low erosion in the laboratory test. A substitute slurry, was found to be 2 to 4 times more erosive than the coal-derived slurry 8 wt% solids. Ranking of materials in the substitute slurry was nearly identical to that in the coal-derived slurry. Three modes of erosion were: ductile cutting; elastic-plastic indentation and fracture; and intergranular fracture. Erosion of a given material was closely related to its microstructure. In the substitute slurry, the angle-dependence of erosion of two forms of SiC, hot-pressed and sintered, were similar, but the sintered material eroded slower. Laser fusing of preplaced powder mixtures can produce cermet-like structures with potential for erosive and sliding wear resistance. TiC particles in Stellite 6 matrix proved less prone to cracking than WC particles in the same matrix. 74 figures, 14 tables.

  15. Modelling challenges for battery materials and electrical energy storage

    NASA Astrophysics Data System (ADS)

    Muller, Richard P.; Schultz, Peter A.

    2013-10-01

    Many vital requirements in world-wide energy production, from the electrification of transportation to better utilization of renewable energy production, depend on developing economical, reliable batteries with improved performance characteristics. Batteries reduce the need for gasoline and liquid hydrocarbons in an electrified transportation fleet, but need to be lighter, longer-lived and have higher energy densities, without sacrificing safety. Lighter and higher-capacity batteries make portable electronics more convenient. Less expensive electrical storage accelerates the introduction of renewable energy to electrical grids by buffering intermittent generation from solar or wind. Meeting these needs will probably require dramatic changes in the materials and chemistry used by batteries for electrical energy storage. New simulation capabilities, in both methods and computational resources, promise to fundamentally accelerate and advance the development of improved materials for electric energy storage. To fulfil this promise significant challenges remain, both in accurate simulations at various relevant length scales and in the integration of relevant information across multiple length scales. This focus section of Modelling and Simulation in Materials Science and Engineering surveys the challenges of modelling for energy storage, describes recent successes, identifies remaining challenges, considers various approaches to surmount these challenges and discusses the potential of these methods for future battery development. Zhang et al begin with atoms and electrons, with a review of first-principles studies of the lithiation of silicon electrodes, and then Fan et al examine the development and use of interatomic potentials to the study the mechanical properties of lithiated silicon in larger atomistic simulations. Marrocchelli et al study ionic conduction, an important aspect of lithium-ion battery performance, simulated by molecular dynamics. Emerging high

  16. Electrically tunable materials for microwave applications

    SciTech Connect

    Ahmed, Aftab Goldthorpe, Irene A.; Khandani, Amir K.

    2015-03-15

    Microwave devices based on tunable materials are of vigorous current interest. Typical applications include phase shifters, antenna beam steering, filters, voltage controlled oscillators, matching networks, and tunable power splitters. The objective of this review is to assist in the material selection process for various applications in the microwave regime considering response time, required level of tunability, operating temperature, and loss tangent. The performance of a variety of material types are compared, including ferroelectric ceramics, polymers, and liquid crystals. Particular attention is given to ferroelectric materials as they are the most promising candidates when response time, dielectric loss, and tunability are important. However, polymers and liquid crystals are emerging as potential candidates for a number of new applications, offering mechanical flexibility, lower weight, and lower tuning voltages.

  17. Electrically tunable materials for microwave applications

    NASA Astrophysics Data System (ADS)

    Ahmed, Aftab; Goldthorpe, Irene A.; Khandani, Amir K.

    2015-03-01

    Microwave devices based on tunable materials are of vigorous current interest. Typical applications include phase shifters, antenna beam steering, filters, voltage controlled oscillators, matching networks, and tunable power splitters. The objective of this review is to assist in the material selection process for various applications in the microwave regime considering response time, required level of tunability, operating temperature, and loss tangent. The performance of a variety of material types are compared, including ferroelectric ceramics, polymers, and liquid crystals. Particular attention is given to ferroelectric materials as they are the most promising candidates when response time, dielectric loss, and tunability are important. However, polymers and liquid crystals are emerging as potential candidates for a number of new applications, offering mechanical flexibility, lower weight, and lower tuning voltages.

  18. PREFACE: Advanced Materials for Demanding Applications

    NASA Astrophysics Data System (ADS)

    McMillan, Alison; Schofield, Stephen; Kelly, Michael

    2015-02-01

    This was a special conference. It was small enough (60+ delegates) but covering a wide range of topics, under a broad end-use focussed heading. Most conferences today either have hundreds or thousands of delegates or are small and very focussed. The topics ranged over composite materials, the testing of durability aspects of materials, and an eclectic set of papers on radar screening using weak ionized plasmas, composites for microvascular applications, composites in space rockets, and materials for spallation neutron sources etc. There were several papers of new characterisation techniques and, very importantly, several papers that started with the end-user requirements leading back into materials selection. In my own area, there were three talks about the technology for the ultra-precise positioning of individual atoms, donors, and complete monolayers to take modern electronics and optoelectronics ideas closer to the market place. The President of the Institute opened with an experience-based talk on translating innovative technology into business. Everyone gave a generous introduction to bring all-comers up to speed with the burning contemporary issues. Indeed, I wish that a larger cohort of first-year engineering PhD students were present to see the full gamut of what takes a physics idea to a success in the market place. I would urge groups to learn from Prof Alison McMillan (a Vice President of the Institute of Physics) and Steven Schofield, to set up conferences of similar scale and breadth. I took in more than I do from mega-meetings, and in greater depth. Professor Michael Kelly Department of Engineering University of Cambridge

  19. Polymers Advance Heat Management Materials for Vehicles

    NASA Technical Reports Server (NTRS)

    2013-01-01

    For 6 years prior to the retirement of the Space Shuttle Program, the shuttles carried an onboard repair kit with a tool for emergency use: two tubes of NOAX, or "good goo," as some people called it. NOAX flew on all 22 flights following the Columbia accident, and was designed to repair damage that occurred on the exterior of the shuttle. Bill McMahon, a structural materials engineer at Marshall Space Flight Center says NASA needed a solution for the widest range of possible damage to the shuttle s exterior thermal protection system. "NASA looked at several options in early 2004 and decided on a sealant. Ultimately, NOAX performed the best and was selected," he says. To prove NOAX would work effectively required hundreds of samples manufactured at Marshall and Johnson, and a concerted effort from various NASA field centers. Johnson Space Center provided programmatic leadership, testing, tools, and crew training; Glenn Research Center provided materials analysis; Langley Research Center provided test support and led an effort to perform large patch repairs; Ames Research Center provided additional testing; and Marshall provided further testing and the site of NOAX manufacturing. Although the sealant never had to be used in an emergency situation, it was tested by astronauts on samples of reinforced carbon-carbon (RCC) during two shuttle missions. (RCC is the thermal material on areas of the shuttle that experience the most heat, such as the nose cone and wing leading edges.) The material handled well on orbit, and tests showed the NOAX patch held up well on RCC.

  20. Advanced Materials and Coatings for Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Miyoshi, Kazuhisa

    2004-01-01

    In the application area of aerospace tribology, researchers and developers must guarantee the highest degree of reliability for materials, components, and systems. Even a small tribological failure can lead to catastrophic results. The absence of the required knowledge of tribology, as Professor H.P. Jost has said, can act as a severe brake in aerospace vehicle systems-and indeed has already done so. Materials and coatings must be able to withstand the aerospace environments that they encounter, such as vacuum terrestrial, ascent, and descent environments; be resistant to the degrading effects of air, water vapor, sand, foreign substances, and radiation during a lengthy service; be able to withstand the loads, stresses, and temperatures encountered form acceleration and vibration during operation; and be able to support reliable tribological operations in harsh environments throughout the mission of the vehicle. This presentation id divided into two sections: surface properties and technology practice related to aerospace tribology. The first section is concerned with the fundamental properties of the surfaces of solid-film lubricants and related materials and coatings, including carbon nanotubes. The second is devoted to applications. Case studies are used to review some aspects of real problems related to aerospace systems to help engineers and scientists to understand the tribological issues and failures. The nature of each problem is analyzed, and the tribological properties are examined. All the fundamental studies and case studies were conducted at the NASA Glenn Research Center.

  1. Cladding and Duct Materials for Advanced Nuclear Recycle Reactors

    SciTech Connect

    Allen, Todd R.; Busby, Jeremy T; Klueh, Ronald L; Maloy, S; Toloczko, M

    2008-01-01

    The expanded use of nuclear energy without risk of nuclear weapons proliferation and with safe nuclear waste disposal is a primary goal of the Global Nuclear Energy Partnership (GNEP). To achieve that goal the GNEP is exploring advanced technologies for recycling spent nuclear fuel that do not separate pure plutonium, and advanced reactors that consume transuranic elements from recycled spent fuel. The GNEP s objectives will place high demands on reactor clad and structural materials. This article discusses the materials requirements of the GNEP s advanced nuclear recycle reactors program.

  2. Advanced STEM Characterization of Nanoscale Materials

    NASA Astrophysics Data System (ADS)

    Dey, Sanchita

    Nanoscale materials are the key structures in determining the properties of many technologically-important materials. Two such important nanoscale materials for different technological applications are investigated in this dissertation. They are: Fischer-Tropsch (FT) catalysts and irradiated metallic bi-layers. Catalytic activity depends on the structural parameters such as size, shape, and distribution on support. On the other hand, the radiation resistance of the model metallic multi-layers is influenced by the presence of interphase, phase-boundaries, and grain-boundaries. The focus of this dissertation is to use different TEM and STEM techniques to understand the structure of these materials. This dissertation begins with a review of the microscopy techniques used in the experiments. Then, in the next two chapters, literature review followed by results and discussions on the two above-mentioned nano materials are presented. Future research directions are included in the concluding chapter. To obtain three-dimensional morphological information of the FT catalysts during reduced/active state, STEM tomography is used. The oxidized state and reduced state is clarified by using STEM-EELS (in the form of spectrum imaging). We used a special vacuum transfer tomography holder and ex-situ gas assembly for reduction, and the reduction parameters are optimized for complete reduction. It was observed that the particle was reduced with 99.99% H2, and at 400°C for 15 minutes. The tomographic results in before-reduction condition depict that the Co-oxide particles are distributed randomly inside the alumina support. After reduction, the tomogram reveals that metallic Co nucleated and sintered towards the surface of the alumina support. The overall metallic Co distribution shows an outward segregation by subsurface diffusion mechanism. In the study of metallic bi-layer, He-irradiated gold twist grain boundary (AuTGB) was chosen as it is one of the least-studied systems in the

  3. Advanced materials and methods for next generation spintronics

    NASA Astrophysics Data System (ADS)

    Siegel, Gene Phillip

    The modern age is filled with ever-advancing electronic devices. The contents of this dissertation continue the desire for faster, smaller, better electronics. Specifically, this dissertation addresses a field known as "spintronics", electronic devices based on an electron's spin, not just its charge. The field of spintronics originated in 1990 when Datta and Das first proposed a "spin transistor" that would function by passing a spin polarized current from a magnetic electrode into a semiconductor channel. The spins in the channel could then be manipulated by applying an electrical voltage across the gate of the device. However, it has since been found that a great amount of scattering occurs at the ferromagnet/semiconductor interface due to the large impedance mismatch that exists between the two materials. Because of this, there were three updated versions of the spintronic transistor that were proposed to improve spin injection: one that used a ferromagnetic semiconductor electrode, one that added a tunnel barrier between the ferromagnet and semiconductor, and one that utilized a ferromagnetic tunnel barrier which would act like a spin filter. It was next proposed that it may be possible to achieve a "pure spin current", or a spin current with no concurrent electric current (i.e., no net flow of electrons). One such method that was discovered is the spin Seebeck effect, which was discovered in 2008 by Uchida et al., in which a thermal gradient in a magnetic material generates a spin current which can be injected into adjacent material as a pure spin current. The first section of this dissertation addresses this spin Seebeck effect (SSE). The goal was to create such a device that both performs better than previously reported devices and is capable of operating without the aid of an external magnetic field. We were successful in this endeavor. The trick to achieving both of these goals was found to be in the roughness of the magnetic layer. A rougher magnetic

  4. An advanced material science payload for GAS

    NASA Technical Reports Server (NTRS)

    Joensson, R.; Wallin, S.; Loeth, K.

    1986-01-01

    The aim of the experiment is to study solidification of different compositions of lead-tin. The weight of the material is quite high: 8 kilograms. Nearly 10% of the payload is sample weight. The dendritic growth and the effect of the absence of natural convection are of particular interest. The results from the flight processed samples will be compared with results from Earth processed samples in order to investigate the influence of the natural convection on the solidification process. The power systems, heat storage and rejection, and mechanical support are discussed in relationship to the scientific requirements.

  5. Advanced Electric Submersible Pump Design Tool for Geothermal Applications

    SciTech Connect

    Xuele Qi; Norman Turnquist; Farshad Ghasripoor

    2012-05-31

    Electrical Submersible Pumps (ESPs) present higher efficiency, larger production rate, and can be operated in deeper wells than the other geothermal artificial lifting systems. Enhanced Geothermal Systems (EGS) applications recommend lifting 300 C geothermal water at 80kg/s flow rate in a maximum 10-5/8-inch diameter wellbore to improve the cost-effectiveness. In this paper, an advanced ESP design tool comprising a 1D theoretical model and a 3D CFD analysis has been developed to design ESPs for geothermal applications. Design of Experiments was also performed to optimize the geometry and performance. The designed mixed-flow type centrifugal impeller and diffuser exhibit high efficiency and head rise under simulated EGS conditions. The design tool has been validated by comparing the prediction to experimental data of an existing ESP product.

  6. Outer Planet Exploration with Advanced Radioisotope Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Oleson, Steven; Gefert, Leon; Patterson, Michael; Schreiber, Jeffrey; Benson, Scott; McAdams, Jim; Ostdiek, Paul

    2002-01-01

    In response to a request by the NASA Deep Space Exploration Technology Program, NASA Glenn Research Center conducted a study to identify advanced technology options to perform a Pluto/Kuiper mission without depending on a 2004 Jupiter Gravity Assist, but still arriving before 2020. A concept using a direct trajectory with small, sub-kilowatt ion thrusters and Stirling radioisotope power systems was shown to allow the same or smaller launch vehicle class as the chemical 2004 baseline and allow a launch slip and still flyby in the 2014 to 2020 timeframe. With this promising result the study was expanded to use a radioisotope power source for small electrically propelled orbiter spacecraft for outer planet targets such as Uranus, Neptune, and Pluto.

  7. Advances in high-tech materials: Datafile III

    SciTech Connect

    Not Available

    1987-01-01

    The important technical developments in materials engineering of 1986 are reported in this survey, which provides details of the inventions and advances achieved in laboratories and universities around the world. The report also forecasts future developments in materials engineering. A list of promising licensing opportunities is included.

  8. Synthesis and characterization of advanced materials for Navy applications

    NASA Technical Reports Server (NTRS)

    Covino, J.; Lee, I.

    1994-01-01

    The synthesis of ceramics and ceramic coatings through the sol-gel process has extensive application with the United States Navy and a broad range of potential commercial applications as well. This paper surveys seven specific applications for which the Navy is investigating these advanced materials. For each area, the synthetic process is described and the characteristics of the materials are discussed.

  9. ADVANCED CERAMIC MATERIALS FOR NEXT-GENERATION NUCLEAR APPLICATIONS

    SciTech Connect

    Marra, J.

    2010-09-29

    proliferation), the worldwide community is working to develop and deploy new nuclear energy systems and advanced fuel cycles. These new nuclear systems address the key challenges and include: (1) extracting the full energy value of the nuclear fuel; (2) creating waste solutions with improved long term safety; (3) minimizing the potential for the misuse of the technology and materials for weapons; (4) continually improving the safety of nuclear energy systems; and (5) keeping the cost of energy affordable.

  10. Electrical properties of materials for high temperature strain gage applications

    NASA Technical Reports Server (NTRS)

    Brittain, John O.

    1989-01-01

    A study was done on the electrical resistance of materials that are potentially useful as resistance strain gages at high temperatures under static strain conditions. Initially a number of binary alloys were investigated. Later, third elements were added to these alloys, all of which were prepared by arc melting. Several transition metals were selected for experimentation, most prepared as thin films. Difficulties with electrical contacts thwarted efforts to extend measurements to the targeted 1000 C, but results obtained did suggest ways of improving the electrical resistance characteristics of certain materials.

  11. Advanced computational research in materials processing for design and manufacturing

    SciTech Connect

    Zacharia, T.

    1995-04-01

    Advanced mathematical techniques and computer simulation play a major role in providing enhanced understanding of conventional and advanced materials processing operations. Development and application of mathematical models and computer simulation techniques can provide a quantitative understanding of materials processes and will minimize the need for expensive and time consuming trial- and error-based product development. As computer simulations and materials databases grow in complexity, high performance computing and simulation are expected to play a key role in supporting the improvements required in advanced material syntheses and processing by lessening the dependence on expensive prototyping and re-tooling. Many of these numerical models are highly compute-intensive. It is not unusual for an analysis to require several hours of computational time on current supercomputers despite the simplicity of the models being studied. For example, to accurately simulate the heat transfer in a 1-m{sup 3} block using a simple computational method requires 10`2 arithmetic operations per second of simulated time. For a computer to do the simulation in real time would require a sustained computation rate 1000 times faster than that achievable by current supercomputers. Massively parallel computer systems, which combine several thousand processors able to operate concurrently on a problem are expected to provide orders of magnitude increase in performance. This paper briefly describes advanced computational research in materials processing at ORNL. Continued development of computational techniques and algorithms utilizing the massively parallel computers will allow the simulation of conventional and advanced materials processes in sufficient generality.

  12. Characterization of advanced preprocessed materials (Hydrothermal)

    SciTech Connect

    Rachel Emerson; Garold Gresham

    2012-09-01

    The initial hydrothermal treatment parameters did not achieve the proposed objective of this effort; the reduction of intrinsic ash in the corn stover. However, liquid fractions from the 170°C treatments was indicative that some of the elements routinely found in the ash that negatively impact the biochemical conversion processes had been removed. After reviewing other options for facilitating ash removal, sodium-citrate (chelating agent) was included in the hydrothermal treatment process, resulting in a 69% reduction in the physiological ash. These results indicated that chelation –hydrothermal treatment is one possible approach that can be utilized to reduce the overall ash content of feedstock materials and having a positive impact on conversion performance.

  13. Experiments investigating advanced materials under thermomechanical loading

    NASA Technical Reports Server (NTRS)

    Bartolotta, Paul A.

    1988-01-01

    Many high temperature aircraft and rocket engine components experience large mechanical loads as well as severe thermal gradients and transients. These nonisothermal conditions are often large enough to cause inelastic deformations, which are the ultimate cause for failure in those parts. A way to alleviate this problem is through improved engine designs based on better predictions of thermomechanical material behavior. To address this concern, an experimental effort was recently initiated within the Hot Section Technology (HOST) program at Lewis. As part of this effort, two new test systems were added to the Fatigue and Structures Lab., which allowed thermomechanical tests to be conducted under closely controlled conditions. These systems are now being used for thermomechanical testing for the Space Station Receiver program, and will be used to support development of metal matrix composites.

  14. Combustion synthesis of advanced composite materials

    NASA Technical Reports Server (NTRS)

    Moore, John J.

    1993-01-01

    Self-propagating high temperature (combustion) synthesis (SHS), has been investigated as a means of producing both dense and expanded (foamed) ceramic and ceramic-metal composites, ceramic powders and whiskers. Several model exothermic combustion synthesis reactions were used to establish the importance of certain reaction parameters, e.g., stoichiometry, green density, combustion mode, particle size, etc. on the control of the synthesis reaction, product morphology and properties. The use of an in situ liquid infiltration technique and the effect of varying the reactants and their stoichiometry to provide a range of reactant and product species i.e., solids, liquids and gases, with varying physical properties e.g., volatility and thermal conductivity, on the microstructure and morphology of synthesized composite materials is discussed. Conducting the combustion synthesis reaction in a reactive gas environment to take advantage of the synergistic effects of combustion synthesis and vapor phase transport is also examined.

  15. Advances in amorphous and nanocrystalline materials

    NASA Astrophysics Data System (ADS)

    Hasegawa, Ryusuke

    2012-10-01

    A new amorphous alloy has been recently introduced which shows a saturation magnetic induction Bs of 1.64 T which is compared with Bs=1.57 T for a currently available Fe-based amorphous alloy and decreased magnetic losses. Such a combination is rare but can be explained in terms of induced magnetic anisotropy being reduced by the alloy's chemistry and its heat treatment. It has been found that the region of magnetization rotation in the new alloy is considerably narrowed, resulting in reduced exciting power in the magnetic devices utilizing the material. Efforts to increase Bs also have been made for nanocrystalline alloys. For example, a nanocrystalline alloy having a composition of Fe80.5Cu1.5Si4B14 shows Bs exceeding 1.8 T. The iron loss at 50 Hz and at 1.6 T induction in a toroidal core of this material is 0.46 W/kg which is 2/3 that of a grain-oriented silicon steel. At 20 kHz/0.2 T excitation, the iron loss is about 60% of that in an Fe-based amorphous alloy which is widely used in power electronics. Another example is a Fe85Si2B8P4Cu1 nanocrystalline alloy with a Bs of 1.8 T, which is reported to exhibit a magnetic core loss of about 0.2 W/kg at 50 Hz and at 1.5 T induction. This article is a review of these new developments and their impacts on energy efficient magnetic devices.

  16. Assessment of Electrical Behavior of Non-Woven Textile Materials

    NASA Astrophysics Data System (ADS)

    Cerovic, Dragana D.; Dojcilovic, Jablan R.; Asanovic, Koviljka A.; Mihailovic, Tatjana V.; Mihajlidi, Tatjana A.

    2010-01-01

    Non-woven textile materials have been increasingly used for a variety of applications in industry and daily life. This imposes a need for the investigation of electrical properties in different conditions of their usage. In the scope of this investigation, electrical conductivity and dielectric properties such as relative dielectric permeability and dielectric loss tangent of various polyester non-woven textile materials were determined. Experimental values of frequency were in the limits of 80 kHz to 2 MHz at relative environmental humidity of 30%. In addition, aimed at discovering the behaviour of investigated material from the aspect of electrical conductivity in various conditions of environmental humidity, the electrical conductance was measured both at 30% and 80% of relative environmental humidity in the electric periodic field at the frequency of 1 MHz. All measurements were realised at the temperature of 30° C. Obtained results showed that with the increase of frequency of electric periodic field electrical conductivity of tested samples increases, while the values of dielectric properties decrease. Furthermore, it was found that the increase of relative environmental humidity provokes the increase of electrical conductivity of tested non-woven samples.

  17. Surface chemical deposition of advanced electronic materials

    NASA Astrophysics Data System (ADS)

    Bjelkevig, Cameron

    The focus of this work was to examine the direct plating of Cu on Ru diffusion barriers for use in interconnect technology and the substrate mediated growth of graphene on boron nitride for use in advanced electronic applications. The electrodeposition of Cu on Ru(0001) and polycrystalline substrates (with and without pretreatment in an iodine containing solution) has been studied by cyclic voltammetry (CV), current--time transient measurements (CTT), in situ electrochemical atomic force microscopy (EC-AFM), and X-ray photoelectron spectroscopy (XPS). The EC-AFM data show that at potentials near the OPD/UPD threshold, Cu crystallites exhibit pronounced growth anisotropy, with lateral dimensions greatly exceeding vertical dimensions. XPS measurements confirmed the presence and stability of adsorbed I on the Ru surface following pre-treatment in a KI/H2SO4 solution and following polarization to at least -200 mV vs. Ag/AgCl. CV data of samples pre-reduced in I-containing electrolyte exhibited a narrow Cu deposition peak in the overpotential region and a UPD peak. The kinetics of the electrodeposited Cu films was investigated by CTT measurements and applied to theoretical models of nucleation. The data indicated that a protective I adlayer may be deposited on an airexposed Ru electrode as the oxide surface is electrochemically reduced, and that this layer will inhibit reformation of an oxide during the Cu electroplating process. A novel method for epitaxial graphene growth directly on a dielectric substrate of systematically variable thickness was studied. Mono/multilayers of BN(111) were grown on Ru(0001) by atomic layer deposition (ALD), exhibiting a flat (non-nanomesh) R30(✓3x✓3) structure. BN(111) was used as a template for growth of graphene by chemical vapor deposition (CVD) of C2H4 at 1000 K. Characterization by LEED, Auger, STM/STS and Raman indicate the graphene is in registry with the BN substrate, and exhibits a HOPG-like 0 eV bandgap density

  18. Materials for advanced rocket engine turbopump turbine blades

    NASA Technical Reports Server (NTRS)

    Chandler, W. T.

    1985-01-01

    A study program was conducted to identify those materials that will provide the greatest benefits as turbine blades for advanced liquid propellant rocket engine turbines and to prepare technology plans for the development of those materials for use in the 1990 through 1995 period. The candidate materials were selected from six classes of materials: single-crystal (SC) superalloys, oxide dispersion-strengthened (ODS) superalloys, rapid solidification processed (RSP) superalloys, directionally solidified eutectic (DSE) superalloys, fiber-reinforced superalloy (FRS) composites, and ceramics. Properties of materials from the six classes were compiled and evaluated and property improvements were projected approximately 5 years into the future for advanced versions of materials in each of the six classes.

  19. SYNTHESIS AND CHARACTERIZATION OF ADVANCED MAGNETIC MATERIALS

    SciTech Connect

    Monica Sorescu

    2004-09-22

    The work described in this grant report was focused mainly on the properties of novel magnetic intermetallics. In the first project, we synthesized several 2:17 intermetallic compounds, namely Nd{sub 2}Fe{sub 15}Si{sub 2}, Nd{sub 2}Fe{sub 15}Al{sub 2}, Nd{sub 2}Fe{sub 15}SiAl and Nd{sub 2}Fe{sub 15}SiMn, as well as several 1:12 intermetallic compounds, such as NdFe{sub 10}Si{sub 2}, NdFe{sub 10}Al{sub 2}, NdFe{sub 10}SiAl and NdFe{sub 10}MnAl. In the second project, seven compositions of Nd{sub x}Fe{sub 100-x-y}B{sub y} ribbons were prepared by a melt spinning method with Nd and B content increasing from 7.3 and 3.6 to 11 and 6, respectively. The alloys were annealed under optimized conditions to obtain a composite material consisting of the hard magnetic Nd{sub 2}Fe{sub 14}B and soft magnetic {alpha}-Fe phases, typical of a spring magnet structure. In the third project, intermetallic compounds of the type Zr{sub 1}Cr{sub 1}Fe{sub 1}T{sub 0.8} with T = Al, Co and Fe were subjected to hydrogenation. In the fourth project, we performed three crucial experiments. In the first experiment, we subjected a mixture of Fe{sub 3}O{sub 4} and Fe (80-20 wt %) to mechanochemical activation by high-energy ball milling, for time periods ranging from 0.5 to 14 hours. In the second experiment, we ball-milled Fe{sub 3}O{sub 4}:Co{sup 2+} (x = 0.1) for time intervals between 2.5 and 17.5 hours. Finally, we exposed a mixture of Fe{sub 3}O{sub 4} and Co (80-20 wt %) to mechanochemical activation for time periods ranging from 0.5 to 10 hours. In all cases, the structural and magnetic properties of the systems involved were elucidated by X-ray diffraction (XRD), Moessbauer spectroscopy and hysteresis loop measurements. The four projects resulted in four papers, which were published in Intermetallics, IEEE Transactions on Magnetics, Journal of Materials Science Letters and Materials Chemistry and Physics. The contributions reveal for the first time in literature the effect of

  20. MATERIALS AND COMPONENT DEVELOPMENT FOR ADVANCED TURBINE SYSTEMS PROJECT SUMMARY

    SciTech Connect

    Alvin, M A

    2010-06-18

    Future hydrogen-fired or oxy-fuel turbines will likely experience an enormous level of thermal and mechanical loading, as turbine inlet temperatures (TIT) approach 1425-1760C (2600-3200F) with pressures of 300-625 psig, respectively. Maintaining the structural integrity of future turbine components under these extreme conditions will require (1) durable thermal barrier coatings (TBCs), (2) high temperature creep resistant metal substrates, and (3) effective cooling techniques. While advances in substrate materials have been limited for the past decades, thermal protection of turbine airfoils in future hydrogen-fired and oxy-fuel turbines will rely primarily on collective advances in the TBCs and aerothermal cooling. To support the advanced turbine technology development, the Office of Research and Development (ORD) at National Energy Technology Laboratory (NETL) has continued its collaborative research efforts with the University of Pittsburgh and West Virginia University, while working in conjunction with commercial material and coating suppliers. This paper presents the technical accomplishments that were made during FY09 in the initial areas of advanced materials, aerothermal heat transfer and non-destructive evaluation techniques for use in advanced land-based turbine applications in the Materials and Component Development for Advanced Turbine Systems project, and introduces three new technology areas high temperature overlayer coating development, diffusion barrier coating development, and oxide dispersion strengthened (ODS) alloy development that are being conducted in this effort.

  1. Integration of advanced nuclear materials separation processes

    SciTech Connect

    Jarvinen, G.D.; Worl, L.A.; Padilla, D.D.; Berg, J.M.; Neu, M.P.; Reilly, S.D.; Buelow, S.

    1998-12-31

    This is the final report of a two-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This project has examined the fundamental chemistry of plutonium that affects the integration of hydrothermal technology into nuclear materials processing operations. Chemical reactions in high temperature water allow new avenues for waste treatment and radionuclide separation.Successful implementation of hydrothermal technology offers the potential to effective treat many types of radioactive waste, reduce the storage hazards and disposal costs, and minimize the generation of secondary waste streams. The focus has been on the chemistry of plutonium(VI) in solution with carbonate since these are expected to be important species in the effluent from hydrothermal oxidation of Pu-containing organic wastes. The authors investigated the structure, solubility, and stability of the key plutonium complexes. Installation and testing of flow and batch hydrothermal reactors in the Plutonium Facility was accomplished. Preliminary testing with Pu-contaminated organic solutions gave effluent solutions that readily met discard requirements. A new effort in FY 1998 will build on these promising initial results.

  2. Simulation Toolkit for Renewable Energy Advanced Materials Modeling

    2013-11-13

    STREAMM is a collection of python classes and scripts that enables and eases the setup of input files and configuration files for simulations of advanced energy materials. The core STREAMM python classes provide a general framework for storing, manipulating and analyzing atomic/molecular coordinates to be used in quantum chemistry and classical molecular dynamics simulations of soft materials systems. The design focuses on enabling the interoperability of materials simulation codes such as GROMACS, LAMMPS and Gaussian.

  3. Numerical Simulations and Optimisation in Forming of Advanced Materials

    NASA Astrophysics Data System (ADS)

    Huétink, J.

    2007-04-01

    With the introduction of new materials as high strength steels, metastable steels and fiber reinforce composites, the need for advanced physically valid constitutive models arises. A biaxial test equipment is developed and applied for the determination of material data as well as for validation of material models. An adaptive through- thickness integration scheme for plate elements is developed, which improves the accuracy of spring back prediction at minimal costs. An optimization strategy is proposed that assists an engineer to model an optimization problem.

  4. Fossil Energy Advanced Research and Technology Development Materials Program

    SciTech Connect

    Cole, N.C.; Judkins, R.R.

    1992-12-01

    Objective of this materials program is to conduct R and D on materials for fossil energy applications with focus on longer-term and generic needs of the various fossil fuel technologies. The projects are organized according to materials research areas: (1) ceramics, (2) new alloys: iron aluminides, advanced austenitics and chromium niobium alloys, and (3) technology development and transfer. Separate abstracts have been prepared.

  5. Advanced Industrial Materials (AIM) Program: Annual progress report FY 1995

    SciTech Connect

    1996-04-01

    In many ways, the Advanced Industrial Materials (AIM) Program underwent a major transformation in Fiscal Year 1995 and these changes have continued to the present. When the Program was established in 1990 as the Advanced Industrial Concepts (AIC) Materials Program, the mission was to conduct applied research and development to bring materials and processing technologies from the knowledge derived from basic research to the maturity required for the end use sectors for commercialization. In 1995, the Office of Industrial Technologies (OIT) made radical changes in structure and procedures. All technology development was directed toward the seven ``Vision Industries`` that use about 80% of industrial energy and generated about 90% of industrial wastes. The mission of AIM has, therefore, changed to ``Support development and commercialization of new or improved materials to improve productivity, product quality, and energy efficiency in the major process industries.`` Though AIM remains essentially a National Laboratory Program, it is essential that each project have industrial partners, including suppliers to, and customers of, the seven industries. Now, well into FY 1996, the transition is nearly complete and the AIM Program remains reasonably healthy and productive, thanks to the superb investigators and Laboratory Program Managers. This Annual Report for FY 1995 contains the technical details of some very remarkable work by the best materials scientists and engineers in the world. Areas covered here are: advanced metals and composites; advanced ceramics and composites; polymers and biobased materials; and new materials and processes.

  6. Simultaneous dynamic electrical and structural measurements of functional materials

    SciTech Connect

    Vecchini, C.; Stewart, M.; Muñiz-Piniella, A.; Wooldridge, J.; Thompson, P.; McMitchell, S. R. C.; Bouchenoire, L.; Brown, S.; Wermeille, D.; Lucas, C. A.; Lepadatu, S.; Bikondoa, O.; Hase, T. P. A.; Lesourd, M.; Dontsov, D.; Cain, M. G.

    2015-10-15

    A new materials characterization system developed at the XMaS beamline, located at the European Synchrotron Radiation Facility in France, is presented. We show that this new capability allows to measure the atomic structural evolution (crystallography) of piezoelectric materials whilst simultaneously measuring the overall strain characteristics and electrical response to dynamically (ac) applied external stimuli.

  7. Code qualification of structural materials for AFCI advanced recycling reactors.

    SciTech Connect

    Natesan, K.; Li, M.; Majumdar, S.; Nanstad, R.K.; Sham, T.-L.

    2012-05-31

    This report summarizes the further findings from the assessments of current status and future needs in code qualification and licensing of reference structural materials and new advanced alloys for advanced recycling reactors (ARRs) in support of Advanced Fuel Cycle Initiative (AFCI). The work is a combined effort between Argonne National Laboratory (ANL) and Oak Ridge National Laboratory (ORNL) with ANL as the technical lead, as part of Advanced Structural Materials Program for AFCI Reactor Campaign. The report is the second deliverable in FY08 (M505011401) under the work package 'Advanced Materials Code Qualification'. The overall objective of the Advanced Materials Code Qualification project is to evaluate key requirements for the ASME Code qualification and the Nuclear Regulatory Commission (NRC) approval of structural materials in support of the design and licensing of the ARR. Advanced materials are a critical element in the development of sodium reactor technologies. Enhanced materials performance not only improves safety margins and provides design flexibility, but also is essential for the economics of future advanced sodium reactors. Code qualification and licensing of advanced materials are prominent needs for developing and implementing advanced sodium reactor technologies. Nuclear structural component design in the U.S. must comply with the ASME Boiler and Pressure Vessel Code Section III (Rules for Construction of Nuclear Facility Components) and the NRC grants the operational license. As the ARR will operate at higher temperatures than the current light water reactors (LWRs), the design of elevated-temperature components must comply with ASME Subsection NH (Class 1 Components in Elevated Temperature Service). However, the NRC has not approved the use of Subsection NH for reactor components, and this puts additional burdens on materials qualification of the ARR. In the past licensing review for the Clinch River Breeder Reactor Project (CRBRP) and the

  8. Advances in Ovonic nickel metal hydride batteries for electric and hybrid vehicles

    SciTech Connect

    Gifford, P.R.; Fetcenko, M.A.; Venkatesan, S.; Corrigan, D.A.; Holland, A.; Dhar, S.K.; Ovshinsky, S.R.

    1994-12-31

    Electric vehicle (EV) technology has been limited by the availability of suitable battery technology to provide the required vehicle range and performance at acceptable cost. Ovonic Battery Co. has developed a proprietary nickel metal hydride battery that provides the required advances in battery technology. This technology is based on the application of multi-element, multi-phase hydride alloys developed for use as negative electrode materials. Ovonic batteries have demonstrated high energy and power density, long cycle life, excellent overcharge and overdischarge tolerance, and wide operating temperature range. An overview of cell and battery performance is presented as well as results discussed for EVs powered by Ovonic batteries. 20 refs.

  9. Fuel, Structural Material and Coolant for an Advanced Fast Micro-Reactor

    NASA Astrophysics Data System (ADS)

    Do Nascimento, J. A.; Duimarães, L. N. F.; Ono, S.

    The use of nuclear reactors in space, seabed or other Earth hostile environment in the future is a vision that some Brazilian nuclear researchers share. Currently, the USA, a leader in space exploration, has as long-term objectives the establishment of a permanent Moon base and to launch a manned mission to Mars. A nuclear micro-reactor is the power source chosen to provide energy for life support, electricity for systems, in these missions. A strategy to develop an advanced micro-reactor technologies may consider the current fast reactor technologies as back-up and the development of advanced fuel, structural and coolant materials. The next generation reactors (GEN-IV) for terrestrial applications will operate with high output temperature to allow advanced conversion cycle, such as Brayton, and hydrogen production, among others. The development of an advanced fast micro-reactor may create a synergy between the GEN-IV and space reactor technologies. Considering a set of basic requirements and materials properties this paper discusses the choice of advanced fuel, structural and coolant materials for a fast micro-reactor. The chosen candidate materials are: nitride, oxide as back-up, for fuel, lead, tin and gallium for coolant, ferritic MA-ODS and Mo alloys for core structures. The next step will be the neutronic and burnup evaluation of core concepts with this set of materials.

  10. Advances in photonics thermal management and packaging materials

    NASA Astrophysics Data System (ADS)

    Zweben, Carl

    2008-02-01

    Heat dissipation, thermal stresses, and cost are key packaging design issues for virtually all semiconductors, including photonic applications such as diode lasers, light-emitting diodes (LEDs), solid state lighting, photovoltaics, displays, projectors, detectors, sensors and laser weapons. Heat dissipation and thermal stresses affect performance and reliability. Copper, aluminum and conventional polymeric printed circuit boards (PCBs) have high coefficients of thermal expansion, which can cause high thermal stresses. Most traditional low-coefficient-of-thermal-expansion (CTE) materials like tungsten/copper, which date from the mid 20 th century, have thermal conductivities that are no better than those of aluminum alloys, about 200 W/m-K. There are an increasing number of low-CTE materials with thermal conductivities ranging between that of copper (400 W/m-K) and 1700 W/m-K, and many other new low-CTE materials with lower thermal conductivities. An important benefit of low-CTE materials is that they allow use of hard solders. Some advanced materials are low cost. Others have the potential to be low cost in high-volume production. High-thermal-conductivity materials enable higher power levels, potentially reducing the number of required devices. Advanced thermal materials can constrain PCB CTE and greatly increase thermal conductivity. This paper reviews traditional packaging materials and advanced thermal management materials. The latter provide the packaging engineer with a greater range of options than in the past. Topics include properties, status, applications, cost, using advanced materials to fix manufacturing problems, and future directions, including composites reinforced with carbon nanotubes and other thermally conductive materials.

  11. Primary electric power generation systems for advanced-technology engines

    NASA Technical Reports Server (NTRS)

    Cronin, M. J.

    1983-01-01

    The advantages of the all electric airplane are discussed. In the all electric airplane the generator is the sole source of electric power; it powers the primary and secondary flight controls, the environmentals, and the landing gear. Five candidates for all electric power systems are discussed and compared. Cost benefits of the all electric airplane are discussed.

  12. Advanced Thermoelectric Materials for Efficient Waste Heat Recovery in Process Industries

    SciTech Connect

    Adam Polcyn; Moe Khaleel

    2009-01-06

    The overall objective of the project was to integrate advanced thermoelectric materials into a power generation device that could convert waste heat from an industrial process to electricity with an efficiency approaching 20%. Advanced thermoelectric materials were developed with figure-of-merit ZT of 1.5 at 275 degrees C. These materials were not successfully integrated into a power generation device. However, waste heat recovery was demonstrated from an industrial process (the combustion exhaust gas stream of an oxyfuel-fired flat glass melting furnace) using a commercially available (5% efficiency) thermoelectric generator coupled to a heat pipe. It was concluded that significant improvements both in thermoelectric material figure-of-merit and in cost-effective methods for capturing heat would be required to make thermoelectric waste heat recovery viable for widespread industrial application.

  13. Advances in Structural Studies of Materials using Scattering Probes

    SciTech Connect

    Huq, Ashfia; Bozin, Emil; Welberry, Dr. Richard

    2010-01-01

    Study of contemporary materials and their remarkable properties is a challenging problem. To understand these complex properties and develop better materials it is essential to understand their structures, as the two are intimately linked. Great advances in materials scattering have been achieved due to the advent of synchrotron and neutron sources along with the availability of high-speed computational algorithms. Materials scientists can now collect data with high resolution, high throughput from very small amount of sample (both single crystal and powder), and analyze vast amount of data to unravel detailed structural description that was not possible before. This article presents some of these great advances in using scattering probes for materials characterization.

  14. Deformation and Damage Studies for Advanced Structural Materials

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Advancements made in understanding deformation and damage of advanced structural materials have enabled the development of new technologies including the attainment of a nationally significant NASA Level 1 Milestone and the provision of expertise to the Shuttle Return to Flight effort. During this collaborative agreement multiple theoretical and experimental research programs, facilitating safe durable high temperature structures using advanced materials, have been conceived, planned, executed. Over 26 publications, independent assessments of structures and materials in hostile environments, were published within this agreement. This attainment has been recognized by 2002 Space Flight Awareness Team Award, 2004 NASA Group Achievement Award and 2003 and 2004 OAI Service Awards. Accomplishments in the individual research efforts are described as follows.

  15. Indiana Advanced Electric Vehicle Training and Education Consortium (I-AEVtec)

    SciTech Connect

    Caruthers, James; Dietz, J.; Pelter, Libby; Chen, Jie; Roberson, Glen; McGinn, Paul; Kizhanipuram, Vinodegopal

    2013-01-31

    The Indiana Advanced Electric Vehicle Training and Education Consortium (I-AEVtec) is an educational partnership between six universities and colleges in Indiana focused on developing the education materials needed to support electric vehicle technology. The I-AEVtec has developed and delivered a number of degree and certificate programs that address various aspects of electric vehicle technology, including over 30 new or significantly modified courses to support these programs. These courses were shared on the SmartEnergyHub. The I-AEVtec program also had a significant outreach to the community with particular focus on K12 students. Finally, the evGrandPrix was established which is a university/college student electric go-kart race, where the students get hands-on experience in designing, building and racing electric vehicles. The evGrandPrix now includes student teams from across the US as well as from Europe and it is currently being held on Opening Day weekend for the Indy500 at the Indianapolis Motor Speedway.

  16. Advanced materials and concepts for energy storage devices

    NASA Astrophysics Data System (ADS)

    Teng, Shiang Jen

    Over the last decade, technological progress and advances in the miniaturization of electronic devices have increased demands for light-weight, high-efficiency, and carbon-free energy storage devices. These energy storage devices are expected to play important roles in automobiles, the military, power plants, and consumer electronics. Two main types of electrical energy storage systems studied in this research are Li ion batteries and supercapacitors. Several promising solid state electrolytes and supercapacitor electrode materials are investigated in this research. The first section of this dissertation is focused on the novel results on pulsed laser annealing of Li7La3Zr2O12 (LLZO). LLZO powders with a tetragonal structure were prepared by a sol-gel technique, then a pulsed laser annealing process was employed to convert the tetragonal powders to cubic LLZO without any loss of lithium. The second section of the dissertation reports on how Li5La 3Nb2O12 (LLNO) was successfully synthesized via a novel molten salt synthesis (MSS) method at the relatively low temperature of 900°C. The low sintering temperature prevented the loss of lithium that commonly occurs during synthesis using conventional solid state or wet chemical reactions. The second type of energy storage device studied is supercapacitors. Currently, research on supercapacitors is focused on increasing their energy densities and lowering their overall production costs by finding suitable electrode materials. The third section of this dissertation details how carbonized woods electrodes were used as supercapacitor electrode materials. A high energy density of 45.6 Wh/kg and a high power density of 2000 W/kg were obtained from the supercapacitor made from carbonized wood electrodes. The high performance of the supercapacitor was discovered to originate from the hierarchical porous structures of the carbonized wood. Finally, the fourth section of this dissertation is on the electrochemical effects of

  17. Advanced materials and electrochemical processes in high-temperature solid electrolytes

    SciTech Connect

    Bates, J.L.; Chick, L.A.; Youngblood, G.E.; Weber, W.J.

    1990-10-01

    Fuel cells for the direct conversion of fossil fuels to electric energy necessitates the use of high-temperature solid electrodes. This study has included: (1) determination of electrical transport, thermal and electrical properties to illucidate the effects of microstructure, phase equilibria, oxygen partial pressure, additives, synthesis and fabrication on these properties; (2) investigation of synthesis and fabrication of advanced oxide materials, such as La{sub 0.9}Sn{sub 0.1}MnO{sub 3}; and (3) application of new analytical techniques using complex impedance coupled with conventional electrochemical methods to study the electrochemical processes and behavior of materials for solid oxide fuel cells and other high-temperature electrolyte electrochemical process. 15 refs., 10 figs., 2 tabs. (BM)

  18. Advanced materials for high-temperature thermoelectric energy conversion

    NASA Technical Reports Server (NTRS)

    Vining, Cronin B.; Vandersande, Jan W.; Wood, Charles

    1992-01-01

    A number of refractory semiconductors are under study at the Jet Propulsion Laboratory for application in thermal to electric energy conversion for space power. The main thrust of the program is to improve or develop materials of high figure of merit and, therefore, high conversion efficiencies over a broad temperature range. Materials currently under investigation are represented by silicon-germanium alloys, lanthanum telluride, and boron carbide. The thermoelectric properties of each of these materials, and prospects for their further improvements, are discussed. Continued progress in thermoelectric materials technology can be expected to yield reliable space power systems with double to triple the efficiency of current state of the art systems.

  19. Efficient, High-Torque Electric Vehicle Motor: Advanced Electric Vehicle Motors with Low or No Rare Earth Content

    SciTech Connect

    2012-01-01

    REACT Project: QM Power will develop a new type of electric motor with the potential to efficiently power future generations of EVs without the use of rare-earth-based magnets. Many of today’s EV motors use rare earth magnets to efficiently provide torque to the wheels. QM Power’s motors would contain magnets that use no rare earth minerals, are light and compact, and can deliver more power with greater efficiency and at reduced cost. Key innovations in this project include a new motor design with iron-based magnetic materials, a new motor control technique, and advanced manufacturing techniques that substantially reduce the cost of the motor. The ultimate goal of this project is to create a cost-effective EV motor that offers the rough peak equivalent of 270 horsepower.

  20. Application of Material Characterization Techniques to Electrical Forensic Analysis

    SciTech Connect

    Mills, T.D.

    2003-03-11

    The application of forensic science techniques to electrical equipment failure investigation has not been widely documented in the engineering world. This paper is intended to share an example of using material characterization techniques to support an initial cause determination of an electrical component failure event. The resulting conclusion supported the initial cause determination and ruled out the possibility of design deficiencies. Thus, the qualification testing of the equipment was allowed to continue to successful completion.

  1. The Electrical Contact for Higher Manganese Silicide Thermoelectric Material

    NASA Astrophysics Data System (ADS)

    Shi, Xinghua; Zamanipour, Zahra; Vashaee, Daryoosh

    2011-03-01

    The Electrical Contact for Higher Manganese Silicide Thermoelectric Material Xinghua Shi, Zahra Zamanipour, Daryoosh Vashaee Several electrical contact materials for Higher Manganese Silicide (HMS) are introduced. HMS is useful thermoelectric material for medium to high temperature applications. We have investigated several materials including Co, Ni, Cr, Ti, Mo, MnSi, MoSi2, and TiSi2 in search of the best contact material to HMS. The low electrical resistivity and reliability of the contact are two important elements to make a high efficient TE device. Moreover, the contact must maintain its chemical, mechanical, thermal, and electrical properties over a broad range of temperature (20C-700C). The investigated elemental metals failed to make reliable contact in terms of mechanical and chemical stability at high temperature. In contrast, the investigated metal silicides showed superior stability over extended operation at high temperature. The thermal stability and strong mechanical bonding of TiSi2 C54 phase and MnSi were specially observed. Their ohmic contact resistance was also within the range of interest over the whole range of temperature (10-5 -10-4 Ω cm2) . This work was supported by AFOSR High Temperature Materials and NSF under contract CBET0933763.

  2. Thermal conductivity and electrical resistivity of porous material

    NASA Technical Reports Server (NTRS)

    Koh, J. C. Y.; Fortini, A.

    1971-01-01

    Thermal conductivity and electrical resistivity of porous materials, including 304L stainless steel Rigimesh, 304L stainless steel sintered spherical powders, and OFHC sintered spherical powders at different porosities and temperatures are reported and correlated. It was found that the thermal conductivity and electrical resistivity can be related to the solid material properties and the porosity of the porous matrix regardless of the matrix structure. It was also found that the Wiedermann-Franz-Lorenz relationship is valid for the porous materials under consideration. For high conductivity materials, the Lorenz constant and the lattice component of conductivity depend on the material and are independent of the porosity. For low conductivity, the lattice component depends on the porosity as well.

  3. Damage Diagnosis in Semiconductive Materials Using Electrical Impedance Measurements

    NASA Technical Reports Server (NTRS)

    Ross, Richard W.; Hinton, Yolanda L.

    2008-01-01

    Recent aerospace industry trends have resulted in an increased demand for real-time, effective techniques for in-flight structural health monitoring. A promising technique for damage diagnosis uses electrical impedance measurements of semiconductive materials. By applying a small electrical current into a material specimen and measuring the corresponding voltages at various locations on the specimen, changes in the electrical characteristics due to the presence of damage can be assessed. An artificial neural network uses these changes in electrical properties to provide an inverse solution that estimates the location and magnitude of the damage. The advantage of the electrical impedance method over other damage diagnosis techniques is that it uses the material as the sensor. Simple voltage measurements can be used instead of discrete sensors, resulting in a reduction in weight and system complexity. This research effort extends previous work by employing finite element method models to improve accuracy of complex models with anisotropic conductivities and by enhancing the computational efficiency of the inverse techniques. The paper demonstrates a proof of concept of a damage diagnosis approach using electrical impedance methods and a neural network as an effective tool for in-flight diagnosis of structural damage to aircraft components.

  4. Electrostatic Discharge Sensitivity and Electrical Conductivity of Composite Energetic Materials

    SciTech Connect

    Michael A. Daniels; Daniel J. Prentice; Chelsea Weir; Michelle L. Pantoya; Gautham Ramachandran; Tim Dallas

    2013-02-01

    Composite energetic material response to electrical stimuli was investigated and a correlation between electrical conductivity and ignition sensitivity was examined. The composites consisted of micrometer particle aluminum combined with another metal, metal oxide, or fluoropolymer. Of the nine tested mixtures, aluminum with copper oxide was the only mixture to ignite by electrostatic discharge with minimum ignition energy (MIE) of 25 mJ and an electrical conductivity of 1246.25 nS; two orders of magnitude higher than the next composite. This study showed a similar trend in MIE for ignition triggered by a discharged spark compared with a thermal hot wire source.

  5. Do Membranes Dream of Electric Tubes? Advanced Membranes Using Carbon Nanotube - Polymer Nanocomposites

    NASA Astrophysics Data System (ADS)

    de Lannoy, Charles-Francois Pedro Claude Karolek Ghislain

    Membrane technologies represent an energy efficient, effective solution for treating municipal and commercial waters/wastewaters. Membranes are predominantly polymer-based and despite steady advances in polymeric materials, they continue to suffer from operational problems including biofouling and breakages. This work addresses these two disparate problems by developing novel CNT-polymer nanocomposite materials that contain variously functionalized carbon nanotubes (fCNTs) in low quantities (<0.5wt%). Several strategies have been employed to achieve highly functional CNT-polymer nanocomposite membranes including blend mixing, ionic charge association, and covalent cross-linking with monomer and oligomer constituents. These CNT-polymer nanocomposite membranes were compared to traditional polymer membranes across various properties including increased Young's Modulus, changes in surface hydrophilicity, fine control over molecular weight cut-off and flux, and surface electrical conductivity. Membranes with high surface electrical conductivity were further tested for their anti-biofouling properties. Finally, CNT stability and polymer compatibility were evaluated throughout membrane manufacture, use, and cleaning. The incorporation of CNTs mixed in bulk phase and linked through ionic associations in polymer matrices showed significant (50%) increases in Young's modulus for certain CNT functionalizations and derivatization percent. Membranes formed with high surface electrical conductivity demonstrated almost complete resistance to biofouling (> 95%) in long-term bacterially challenged experiments. CNTs and polymer mixtures that lacked covalent or ionic bonds were susceptible to significant (up to 10%) loss of CNTs during membrane non-solvent gelation and aggressive chemical cleaning treatment. Functionalized carbon nanotubes endow polymer membranes with their unique strength and electrically conductive properties. These added properties were demonstrated to greatly

  6. Soft computing in design and manufacturing of advanced materials

    NASA Technical Reports Server (NTRS)

    Cios, Krzysztof J.; Baaklini, George Y; Vary, Alex

    1993-01-01

    The potential of fuzzy sets and neural networks, often referred to as soft computing, for aiding in all aspects of manufacturing of advanced materials like ceramics is addressed. In design and manufacturing of advanced materials, it is desirable to find which of the many processing variables contribute most to the desired properties of the material. There is also interest in real time quality control of parameters that govern material properties during processing stages. The concepts of fuzzy sets and neural networks are briefly introduced and it is shown how they can be used in the design and manufacturing processes. These two computational methods are alternatives to other methods such as the Taguchi method. The two methods are demonstrated by using data collected at NASA Lewis Research Center. Future research directions are also discussed.

  7. Conceptual design of a solar electric advanced Stirling power system

    NASA Astrophysics Data System (ADS)

    White, M. A.; Brown, A. T.

    1987-02-01

    The objective is to develop a high confidence conceptual design for a free-piston Stirling engine based system designed to deliver 25 kW of three-phase electric power to a utility grid when coupled to the 11 meter Test Bed Concentrator (TBC) at SNLA. Further objectives include a design life of 60,000 hours, minimum life cycle cost and dynamic balancing. The approach used to achieve these objectives is to utilize a hermetically sealed Stirling hydraulic concept based on technology developed to an advanced level during the past 19 years for an artificial heart power source. Such engines and critical metal bellows components have demonstrated operating times in the desired range. This approach provides full film hydraulic lubrication of all sliding parts, simple construction with conventional manufacturing tolerances, proven hydraulically coupled counterbalancing, and simple but effective power control to follow insolation variations. Other advantages include use of commercially available hydraulic motors and rotary alternators which can be placed on the ground to minimize suspended weight. The output from several engine/concentrator modules can be directed to one large motor/alternator for further cost savings. Three monthly progress reports for the same period, January 1 to January 31, 1987, are compiled within this document.

  8. Advanced Electrical, Optical and Data Communication Infrastructure Development

    SciTech Connect

    Simon Cobb

    2011-04-30

    The implementation of electrical and IT infrastructure systems at the North Carolina Center for Automotive Research , Inc. (NCCAR) has achieved several key objectives in terms of system functionality, operational safety and potential for ongoing research and development. Key conclusions include: (1) The proven ability to operate a high speed wireless data network over a large 155 acre area; (2) Node to node wireless transfers from access points are possible at speeds of more than 50 mph while maintaining high volume bandwidth; (3) Triangulation of electronic devices/users is possible in areas with overlapping multiple access points, outdoor areas with reduced overlap of access point coverage considerably reduces triangulation accuracy; (4) Wireless networks can be adversely affected by tree foliage, pine needles are a particular challenge due to the needle length relative to the transmission frequency/wavelength; and (5) Future research will use the project video surveillance and wireless systems to further develop automated image tracking functionality for the benefit of advanced vehicle safety monitoring and autonomous vehicle control through 'vehicle-to-vehicle' and 'vehicle-to-infrastructure' communications. A specific advantage realized from this IT implementation at NCCAR is that NC State University is implementing a similar wireless network across Centennial Campus, Raleigh, NC in 2011 and has benefited from lessons learned during this project. Consequently, students, researchers and members of the public will be able to benefit from a large scale IT implementation with features and improvements derived from this NCCAR project.

  9. Progress in advanced high temperature turbine materials, coatings, and technology

    NASA Technical Reports Server (NTRS)

    Freche, J. C.; Ault, G. M.

    1978-01-01

    Advanced materials, coatings, and cooling technology is assessed in terms of improved aircraft turbine engine performance. High cycle operating temperatures, lighter structural components, and adequate resistance to the various environmental factors associated with aircraft gas turbine engines are among the factors considered. Emphasis is placed on progress in development of high temperature materials for coating protection against oxidation, hot corrosion and erosion, and in turbine cooling technology. Specific topics discussed include metal matrix composites, superalloys, directionally solidified eutectics, and ceramics.

  10. MATERIALS AND COMPONENT DEVELOPMENT FOR ADVANCED TURBINE SYSTEMS

    SciTech Connect

    M. A. Alvin

    2009-06-12

    Future hydrogen-fired or oxy-fuel turbines will likely experience an enormous level of thermal and mechanical loading, as turbine inlet temperatures (TIT) approach 1425-1760ºC with pressures of 300-625 psig, respectively. Maintaining the structural integrity of future turbine components under these extreme conditions will require durable thermal barrier coatings (TBCs), high temperature creep resistant metal substrates, and effective cooling techniques. While advances in substrate materials have been limited for the past decades, thermal protection of turbine airfoils in future hydrogen-fired and oxy-fuel turbines will rely primarily on collective advances in TBCs and aerothermal cooling. To support the advanced turbine technology development, the National Energy Technology Laboratory (NETL) at the Office of Research and Development (ORD) has initiated a research project effort in collaboration with the University of Pittsburgh (UPitt), and West Virginia University (WVU), working in conjunction with commercial material and coating suppliers, to develop advanced materials, aerothermal configurations, as well as non-destructive evaluation techniques for use in advanced land-based gas turbine applications. This paper reviews technical accomplishments recently achieved in each of these areas.

  11. ADVANCED HOT SECTION MATERIALS AND COATINGS TEST RIG

    SciTech Connect

    Scott Reome; Dan Davies

    2004-04-30

    The Hyperbaric Advanced Hot Section Materials & Coating Test Rig program provides design and implementation of a laboratory rig capable of simulating the hot gas path conditions of coal-gas fired industrial gas turbine engines. The principal activity during this reporting period were the evaluation of syngas combustor concepts, the evaluation of test section concepts and the selection of the preferred rig configuration.

  12. Advanced Hot Section Materials and Coatings Test Rig

    SciTech Connect

    Dan Davies

    2004-10-30

    The Hyperbaric Advanced Hot Section Materials & Coating Test Rig program provides design and implementation of a laboratory rig capable of simulating the hot gas path conditions of coal-gas fired industrial gas turbine engines. The principal activities during this reporting period were the continuation of test section detail design and developing specifications for auxiliary systems and facilities.

  13. Advanced Packaging Materials and Techniques for High Power TR Module: Standard Flight vs. Advanced Packaging

    NASA Technical Reports Server (NTRS)

    Hoffman, James Patrick; Del Castillo, Linda; Miller, Jennifer; Jenabi, Masud; Hunter, Donald; Birur, Gajanana

    2011-01-01

    The higher output power densities required of modern radar architectures, such as the proposed DESDynI [Deformation, Ecosystem Structure, and Dynamics of Ice] SAR [Synthetic Aperture Radar] Instrument (or DSI) require increasingly dense high power electronics. To enable these higher power densities, while maintaining or even improving hardware reliability, requires advances in integrating advanced thermal packaging technologies into radar transmit/receive (TR) modules. New materials and techniques have been studied and compared to standard technologies.

  14. Electrically conductive and thermally conductive materials for electronic packaging

    NASA Astrophysics Data System (ADS)

    Liu, Zongrong

    The aim of this dissertation is to develop electrically or thermally conductive materials that are needed for electronic packaging and microelectronic cooling. These materials are in the form of coatings and are made from pastes. The research work encompasses paste formulation, studying the process of converting a paste to a conductive material, relating the processing conditions to the structure and performance, and evaluating performance attributes that are relevant to the application of these conductive materials. The research has resulted in new information that is valuable to the microelectronic industry. Work on electrically conductive materials emphasizes the development of electrical interconnection materials in the form of air-firable glass-free silver-based electrically conductive thick films, which use the Ti-Al alloy as the binder and are in contrast to conventional films that use glass as the binder. The air-firability, as enabled by minor additions of tin and zinc to the paste, is in contrast to previous glass-free films that are not firable. The recommended firing condition is 930°C in air. The organic vehicle in the paste comprises ethyl cellulose, which undergoes thermal decomposition during burnout of the paste. The ethyl cellulose is dissolved in ether, which facilitates the burnout. Excessive ethyl cellulose hinders the burnout. A higher heating rate results in more residue after burnout. The presence of silver particles facilitates drying and burnout. Firing in air gives lower resistivity than firing in oxygen. Firing in argon gives poor films. Compared to conventional films that use glass as the binder, these films, when appropriately fired, exhibit lower electrical resistivity (2.5 x 10-6 O.cm) and higher scratch resistance. Work on thermally conductive materials addresses thermal interface materials, which are materials placed at the interface between a heat sink and a heat source for the purpose of improving the thermal contact. Heat

  15. Materials/manufacturing element of the Advanced Turbine Systems Program

    SciTech Connect

    Karnitz, M.A.; Holcomb, R.S.; Wright, I.G.

    1995-10-01

    The technology based portion of the Advanced Turbine Systems Program (ATS) contains several subelements which address generic technology issues for land-based gas-turbine systems. One subelement is the Materials/Manufacturing Technology Program which is coordinated by DOE-Oak Ridge Operations and Oak Ridge National Laboratory (ORNL). The work in this subelement is being performed predominantly by industry with assistance from universities and the national laboratories. Projects in this subelement are aimed toward hastening the incorporation of new materials and components in gas turbines. A materials/manufacturing plan was developed in FY 1994 with input from gas turbine manufacturers, materials suppliers, universities, and government laboratories. The plan outlines seven major subelements which focus on materials issues and manufacturing processes. Work is currently under way in four of the seven major subelements. There are now major projects on coatings and process development, scale-up of single crystal airfoil manufacturing technology, materials characterization, and technology information exchange.

  16. New Materials for the Repair of Polyimide Electrical Wire Insulation

    NASA Technical Reports Server (NTRS)

    2008-01-01

    Two viable polyimide backbone materials have been identified that will allow the repair of polyimide electrical wire insulation found on the Space Shuttle and other aging aircraft. This identification is the outcome of ongoing efforts to assess the viability of using such polyimides and polyimide precursors (polyamic acids [PAAs]) as repair materials for aging polyimide electrical wire insulation. These repair materials were selected because they match the chemical makeup of the underlying wire insulation as closely as possible. This similarity allows for maximum compatibility, coupled with the outstanding physical properties of polyimides. The two polyimide backbone materials allow the polymer to be extremely flexible and to melt at low temperatures. A polymer chain end capping group that allows the polymer to crosslink into a nonflowable repair upon curing at around 200 C was also identified.

  17. Corrosion performance of advanced structural materials in sodium.

    SciTech Connect

    Natesan, K.; Momozaki, Y.; Li, M.; Rink, D.L.

    2012-05-16

    This report gives a description of the activities in design, fabrication, construction, and assembling of a pumped sodium loop for the sodium compatibility studies on advanced structural materials. The work is the Argonne National Laboratory (ANL) portion of the effort on the work project entitled, 'Sodium Compatibility of Advanced Fast Reactor Materials,' and is a part of Advanced Materials Development within the Reactor Campaign. The objective of this project is to develop information on sodium corrosion compatibility of advanced materials being considered for sodium reactor applications. This report gives the status of the sodium pumped loop at Argonne National Laboratory, the specimen details, and the technical approach to evaluate the sodium compatibility of advanced structural alloys. This report is a deliverable from ANL in FY2010 (M2GAN10SF050302) under the work package G-AN10SF0503 'Sodium Compatibility of Advanced Fast Reactor Materials.' Two reports were issued in 2009 (Natesan and Meimei Li 2009, Natesan et al. 2009) which examined the thermodynamic and kinetic factors involved in the purity of liquid sodium coolant for sodium reactor applications as well as the design specifications for the ANL pumped loop for testing advanced structural materials. Available information was presented on solubility of several metallic and nonmetallic elements along with a discussion of the possible mechanisms for the accumulation of impurities in sodium. That report concluded that the solubility of many metals in sodium is low (<1 part per million) in the temperature range of interest in sodium reactors and such trace amounts would not impact the mechanical integrity of structural materials and components. The earlier report also analyzed the solubility and transport mechanisms of nonmetallic elements such as oxygen, nitrogen, carbon, and hydrogen in laboratory sodium loops and in reactor systems such as Experimental Breeder Reactor-II, Fast Flux Test Facility, and

  18. Advanced Propulsion Research Interest in Materials for Propulsion

    NASA Technical Reports Server (NTRS)

    Cole, John

    2003-01-01

    This viewgraph presentation provides an overview of material science and technology in the area of propulsion energetics. The authors note that conventional propulsion systems are near peak performance and further refinements in manufacturing, engineering design and materials will only provide incremental increases in performance. Energetic propulsion technologies could potential solve the problems of energy storage density and energy-to-thrust conversion efficiency. Topics considered include: the limits of thermal propulsion systems, the need for energetic propulsion research, emerging energetic propulsion technologies, materials research needed for advanced propulsion, and potential research opportunities.

  19. Materials/manufacturing element of the Advanced Turbine System Program

    SciTech Connect

    Karnitz, M.A.; Devan, J.H.; Holcomb, R.S.; Ferber, M.K.; Harrison, R.W.

    1994-08-01

    One of the supporting elements of the Advanced Turbine Systems (ATS) Program is the materials/manufacturing technologies task. The objective of this element is to address critical materials issues for both industrial and utility gas turbines. DOE Oak Ridge Operations Office (ORO) will manage this element of the program, and a team from DOE-ORO and Oak Ridge National Laboratory is coordinating the planning for the materials/manufacturing effort. This paper describes that planning activity which is in the early stages.

  20. Ceramic matrix composites -- Advanced high-temperature structural materials

    SciTech Connect

    Lowden, R.A.; Ferber, M.K.; Hellmann, J.R.; Chawla, K.K.; DiPietro, S.G.

    1995-10-01

    This symposium on Ceramic Matrix Composites: Advanced High-Temperature Structural Materials was held at the 1994 MRS Fall Meeting in Boston, Massachusetts on November 28--December 2. The symposium was sponsored by the Department of Energy`s Office of Industrial Technology`s Continuous Fiber Ceramic Composites Program, the Air Force Office of Scientific Research, and NASA Lewis Research Center. Among the competing materials for advanced, high-temperature applications, ceramic matrix composites are leading candidates. The symposium was organized such that papers concerning constituents--fibers and matrices--were presented first, followed by composite processing, modeling of mechanical behavior, and thermomechanical testing. More stable reinforcements are necessary to enhance the performance and life of fiber-reinforced ceramic composites, and to ensure final acceptance of these materials for high-temperature applications. Encouraging results in the areas of polymer-derived SiC fibers and single crystal oxide filaments were given, suggesting composites with improved thermomechanical properties and stability will be realized in the near future. The significance of the fiber-matrix interface in the design and performance of these materials is evident. Numerous mechanical models to relate interface properties to composite behavior, and interpret test methods and data, were enthusiastically discussed. One issue of great concern for any advanced material for use in extreme environments is stability. This theme arose frequently throughout the symposium and was the topic of focus on the final day. Fifty nine papers have been processed separately for inclusion on the data base.

  1. Bridging Microstructure, Properties and Processing of Polymer Based Advanced Materials

    SciTech Connect

    Li, Dongsheng; Ahzi, Said; Khaleel, Mohammad A.

    2012-01-01

    This is a guest editorial for a special issue in Journal of Engineering Materials and Technology. The papers collected in this special issue emphasize significant challenges, current approaches and future strategies necessary to advance the development of polymer-based materials. They were partly presented at the symposium of 'Bridging microstructure, properties and processing of polymer based advanced materials' in the TMS 2011 annual conference meeting, which was held in San Diego, US, on Feb 28 to March 3, 2011. This symposium was organized by the Pacific Northwest National Laboratory (USA) and the Institute of Mechanics of Fluids and Solids of the University of Strasbourg (France). The organizers were D.S. Li, S. Ahzi, and M. Khaleel.

  2. High resolution computed tomography of advanced composite and ceramic materials

    NASA Technical Reports Server (NTRS)

    Yancey, R. N.; Klima, S. J.

    1991-01-01

    Advanced composite and ceramic materials are being developed for use in many new defense and commercial applications. In order to achieve the desired mechanical properties of these materials, the structural elements must be carefully analyzed and engineered. A study was conducted to evaluate the use of high resolution computed tomography (CT) as a macrostructural analysis tool for advanced composite and ceramic materials. Several samples were scanned using a laboratory high resolution CT scanner. Samples were also destructively analyzed at the locations of the scans and the nondestructive and destructive results were compared. The study provides useful information outlining the strengths and limitations of this technique and the prospects for further research in this area.

  3. Elevated Temperature Testing and Modeling of Advanced Toughened Ceramic Materials

    NASA Technical Reports Server (NTRS)

    Keith, Theo G.

    2005-01-01

    The purpose of this report is to provide a final report for the period of 12/1/03 through 11/30/04 for NASA Cooperative Agreement NCC3-776, entitled "Elevated Temperature Testing and Modeling of Advanced Toughened Ceramic Materials." During this final period, major efforts were focused on both the determination of mechanical properties of advanced ceramic materials and the development of mechanical test methodologies under several different programs of the NASA-Glenn. The important research activities made during this period are: 1. Mechanical properties evaluation of two gas-turbine grade silicon nitrides. 2) Mechanical testing for fuel-cell seal materials. 3) Mechanical properties evaluation of thermal barrier coatings and CFCCs and 4) Foreign object damage (FOD) testing.

  4. Institute for Advanced Materials at University of Louisville

    SciTech Connect

    Sunkara, Mahendra; Sumaneskara, Gamini; Starr, Thomas L; Willing, G A; Robert W, Cohn

    2009-10-29

    In this project, a university-wide, academic center has been established entitled Institute for Advanced Materials and Renewable Energy. In this institute, a comprehensive materials characterization facility has been established by co-locating several existing characterization equipment and acquiring several state of the art instrumentation such as field emission transmission electron microscope, scanning electron microscope, high resolution X-ray diffractometer, Particle Size Distribution/Zeta Potential measurement system, and Ultra-microtome for TEM specimen. In addition, a renewable energy conversion and storage research facility was also established by acquiring instrumentation such as UV-Vis absorption spectroscopy, Atomic Layer Deposition reactor, Solar light simulator, oxygen-free glove box, potentiostat/galvanostats and other miscellaneous items. The institute is staffed with three full-time staff members (one senior research technologist, a senior PhD level research scientist and a junior research scientist) to enable proper use of the techniques. About thirty faculty, fifty graduate students and several researchers access the facilities on a routine basis. Several industry R&D organizations (SudChemie, Optical Dynamics and Hexion) utilize the facility. The established Institute for Advanced Materials at UofL has three main objectives: (a) enable a focused research effort leading to the rapid discovery of new materials and processes for advancing alternate energy conversion and storage technologies; (b) enable offering of several laboratory courses on advanced materials science and engineering; and (c) develop university-industry partnerships based on the advanced materials research. The Institute's efforts were guided by an advisory board comprising eminent researchers from outside KY. Initial research efforts were focused on the discovery of new materials and processes for solar cells and Li ion battery electrodes. Initial sets of results helped PIs to

  5. Recent Advances in Two-Dimensional Materials Beyond Graphene

    SciTech Connect

    Meunier, Vincent; Sumpter, Bobby G.; Terrones Maldonado, Mauricio; Terrones Maldonado, Humberto; Liang, Liangbo; Cooper, Valentino R.; Bhimanapati, Ganesh; Lin, Zhong; Jung, Yeongwoong; Cha, Judy; Das, Saptarshi; Xiao, Di; Son, Youngwoo; Strano, Michael; Louie, Steven G.; Ringe, Emilie; Xia, Fengnian; Wang, Yeliang; Akinwande, Deji; Zhu, Jun; Schuller, John; Schaak, Raymond; Robinson, Joshua A

    2015-11-06

    The isolation of graphene in 2004 by peeling apart the atomically-thin sheets that comprise graphite was a defining moment for the birth of a field: Two-dimensional (2D) materials. In recent years, there has been a rapidly increasing number of papers focusing on non-graphene layered materials, including transition-metal dichalcogenides (TMDs), because of the new properties and applications that emerge upon 2D confinement. Here we review significant recent advances and important new developments in 2D materials beyond graphene . We provide insight into the theoretical modeling and understanding of the van der Waals forces that hold together the 2D layers in bulk solids, as well as their excitonic properties and growth morphologies. Additionally, we highlight recent breakthroughs in TMD synthesis and characterization and discuss the newest families of 2D materials, including monoelement 2D materials (i.e., silicene, phosphorene, etc.) and transition metal carbide- and carbon nitride-based MXenes. We then discuss the doping and functionalization of 2D materials beyond graphene, which enable device applications, followed by advances in electronic, optoelectronic, and magnetic devices and theory. Finally, we provide perspectives on the future of 2D materials beyond graphene.

  6. Recent Advances in Two-Dimensional Materials Beyond Graphene

    DOE PAGESBeta

    Meunier, Vincent; Sumpter, Bobby G.; Terrones Maldonado, Mauricio; Terrones Maldonado, Humberto; Liang, Liangbo; Cooper, Valentino R.; Bhimanapati, Ganesh; Lin, Zhong; Jung, Yeongwoong; Cha, Judy; et al

    2015-11-06

    The isolation of graphene in 2004 by peeling apart the atomically-thin sheets that comprise graphite was a defining moment for the birth of a field: Two-dimensional (2D) materials. In recent years, there has been a rapidly increasing number of papers focusing on non-graphene layered materials, including transition-metal dichalcogenides (TMDs), because of the new properties and applications that emerge upon 2D confinement. Here we review significant recent advances and important new developments in 2D materials beyond graphene . We provide insight into the theoretical modeling and understanding of the van der Waals forces that hold together the 2D layers in bulkmore » solids, as well as their excitonic properties and growth morphologies. Additionally, we highlight recent breakthroughs in TMD synthesis and characterization and discuss the newest families of 2D materials, including monoelement 2D materials (i.e., silicene, phosphorene, etc.) and transition metal carbide- and carbon nitride-based MXenes. We then discuss the doping and functionalization of 2D materials beyond graphene, which enable device applications, followed by advances in electronic, optoelectronic, and magnetic devices and theory. Finally, we provide perspectives on the future of 2D materials beyond graphene.« less

  7. Recent Advances in Two-Dimensional Materials beyond Graphene.

    PubMed

    Bhimanapati, Ganesh R; Lin, Zhong; Meunier, Vincent; Jung, Yeonwoong; Cha, Judy; Das, Saptarshi; Xiao, Di; Son, Youngwoo; Strano, Michael S; Cooper, Valentino R; Liang, Liangbo; Louie, Steven G; Ringe, Emilie; Zhou, Wu; Kim, Steve S; Naik, Rajesh R; Sumpter, Bobby G; Terrones, Humberto; Xia, Fengnian; Wang, Yeliang; Zhu, Jun; Akinwande, Deji; Alem, Nasim; Schuller, Jon A; Schaak, Raymond E; Terrones, Mauricio; Robinson, Joshua A

    2015-12-22

    The isolation of graphene in 2004 from graphite was a defining moment for the "birth" of a field: two-dimensional (2D) materials. In recent years, there has been a rapidly increasing number of papers focusing on non-graphene layered materials, including transition-metal dichalcogenides (TMDs), because of the new properties and applications that emerge upon 2D confinement. Here, we review significant recent advances and important new developments in 2D materials "beyond graphene". We provide insight into the theoretical modeling and understanding of the van der Waals (vdW) forces that hold together the 2D layers in bulk solids, as well as their excitonic properties and growth morphologies. Additionally, we highlight recent breakthroughs in TMD synthesis and characterization and discuss the newest families of 2D materials, including monoelement 2D materials (i.e., silicene, phosphorene, etc.) and transition metal carbide- and carbon nitride-based MXenes. We then discuss the doping and functionalization of 2D materials beyond graphene that enable device applications, followed by advances in electronic, optoelectronic, and magnetic devices and theory. Finally, we provide perspectives on the future of 2D materials beyond graphene. PMID:26544756

  8. PREFACE: 7th EEIGM International Conference on Advanced Materials Research

    NASA Astrophysics Data System (ADS)

    Joffe, Roberts

    2013-12-01

    The 7th EEIGM Conference on Advanced Materials Research (AMR 2013) was held at Luleå University of Technology on the 21-22 March 2013 in Luleå, SWEDEN. This conference is intended as a meeting place for researchers involved in the EEIGM programme, in the 'Erasmus Mundus' Advanced Materials Science and Engineering Master programme (AMASE) and the 'Erasmus Mundus' Doctoral Programme in Materials Science and Engineering (DocMASE). This is great opportunity to present their on-going research in the various fields of Materials Science and Engineering, exchange ideas, strengthen co-operation as well as establish new contacts. More than 60 participants representing six countries attended the meeting, in total 26 oral talks and 19 posters were presented during two days. This issue of IOP Conference Series: Materials Science and Engineering presents a selection of articles from EEIGM-7 conference. Following tradition from previous EEIGM conferences, it represents the interdisciplinary nature of Materials Science and Engineering. The papers presented in this issue deal not only with basic research but also with applied problems of materials science. The presented topics include theoretical and experimental investigations on polymer composite materials (synthetic and bio-based), metallic materials and ceramics, as well as nano-materials of different kind. Special thanks should be directed to the senior staff of Division of Materials Science at LTU who agreed to review submitted papers and thus ensured high scientific level of content of this collection of papers. The following colleagues participated in the review process: Professor Lennart Walström, Professor Roberts Joffe, Professor Janis Varna, Associate Professor Marta-Lena Antti, Dr Esa Vuorinen, Professor Aji Mathew, Professor Alexander Soldatov, Dr Andrejs Purpurs, Dr Yvonne Aitomäki, Dr Robert Pederson. Roberts Joffe October 2013, Luleå Conference photograph EEIGM7 conference participants, 22 March 2013 The PDF

  9. Materials and Component Development for Advanced Turbine Systems

    SciTech Connect

    Alvin, M.A.; Pettit, F.; Meier, G.; Yanar, N.; Chyu, M.; Mazzotta, D.; Slaughter, W.; Karaivanov, V.; Kang, B.; Feng, C.; Chen, R.; Fu, T-C.

    2008-10-01

    In order to meet the 2010-2020 DOE Fossil Energy goals for Advanced Power Systems, future oxy-fuel and hydrogen-fired turbines will need to be operated at higher temperatures for extended periods of time, in environments that contain substantially higher moisture concentrations in comparison to current commercial natural gas-fired turbines. Development of modified or advanced material systems, combined with aerothermal concepts are currently being addressed in order to achieve successful operation of these land-based engines. To support the advanced turbine technology development, the National Energy Technology Laboratory (NETL) has initiated a research program effort in collaboration with the University of Pittsburgh (UPitt), and West Virginia University (WVU), working in conjunction with commercial material and coating suppliers as Howmet International and Coatings for Industry (CFI), and test facilities as Westinghouse Plasma Corporation (WPC) and Praxair, to develop advanced material and aerothermal technologies for use in future oxy-fuel and hydrogen-fired turbine applications. Our program efforts and recent results are presented.

  10. Review of the proposed materials of construction for the SBWR and AP600 advanced reactors

    SciTech Connect

    Diercks, D.R.; Shack, W.J.; Chung, H.M.; Kassner, T.F.

    1994-06-01

    Two advanced light water reactor (LWR) concepts, namely the General Electric Simplified Boiling Water Reactor (SBWR) and the Westinghouse Advanced Passive 600 MWe Reactor (AP600), were reviewed in detail by Argonne National Laboratory. The objectives of these reviews were to (a) evaluate proposed advanced-reactor designs and the materials of construction for the safety systems, (b) identify all aging and environmentally related degradation mechanisms for the materials of construction, and (c) evaluate from the safety viewpoint the suitability of the proposed materials for the design application. Safety-related systems selected for review for these two LWRs included (a) reactor pressure vessel, (b) control rod drive system and reactor internals, (c) coolant pressure boundary, (d) engineered safety systems, (e) steam generators (AP600 only), (f) turbines, and (g) fuel storage and handling system. In addition, the use of cobalt-based alloys in these plants was reviewed. The selected materials for both reactors were generally sound, and no major selection errors were found. It was apparent that considerable thought had been given to the materials selection process, making use of lessons learned from previous LWR experience. The review resulted in the suggestion of alternate an possibly better materials choices in a number of cases, and several potential problem areas have been cited.

  11. Synthesis and characterization of advanced materials for Navy applications

    SciTech Connect

    Covino, J.

    1993-12-31

    This paper addresses the synthesis of ceramics and ceramic coatings, via the sol-gel process for use in specific Navy applications. Among the specific applications are: coatings for electrocromic devices; laser gyro bodies, hermetic coatings for optical fibers for use in ocean environments; coating development for advanced light weight structural applications; and incorporation of organic and inorganic dyes in silica based ceramics for laser applications. It will also address the characterization of these systems as well as advanced structural materials with respect to durability, chemical stability, optical properties and other properties which are more specific to their applications and end use.

  12. Advanced Materials for High Temperature, High Performance, Wide Bandgap Power Modules

    NASA Astrophysics Data System (ADS)

    O'Neal, Chad B.; McGee, Brad; McPherson, Brice; Stabach, Jennifer; Lollar, Richard; Liederbach, Ross; Passmore, Brandon

    2016-01-01

    Advanced packaging materials must be utilized to take full advantage of the benefits of the superior electrical and thermal properties of wide bandgap power devices in the development of next generation power electronics systems. In this manuscript, the use of advanced materials for key packaging processes and components in multi-chip power modules will be discussed. For example, to date, there has been significant development in silver sintering paste as a high temperature die attach material replacement for conventional solder-based attach due to the improved thermal and mechanical characteristics as well as lower processing temperatures. In order to evaluate the bond quality and performance of this material, shear strength, thermal characteristics, and void quality for a number of silver sintering paste materials were analyzed as a die attach alternative to solder. In addition, as high voltage wide bandgap devices shift from engineering samples to commercial components, passivation materials become key in preventing premature breakdown in power modules. High temperature, high dielectric strength potting materials were investigated to be used to encapsulate and passivate components internal to a power module. The breakdown voltage up to 30 kV and corresponding leakage current for these materials as a function of temperature is also presented. Lastly, high temperature plastic housing materials are important for not only discrete devices but also for power modules. As the operational temperature of the device and/or ambient temperature increases, the mechanical strength and dielectric properties are dramatically reduced. Therefore, the electrical characteristics such as breakdown voltage and leakage current as a function of temperature for housing materials are presented.

  13. PREFACE: 6th EEIGM International Conference on Advanced Materials Research

    NASA Astrophysics Data System (ADS)

    Horwat, David; Ayadi, Zoubir; Jamart, Brigitte

    2012-02-01

    The 6th EEIGM Conference on Advanced Materials Research (AMR 2011) was held at the European School of Materials Engineering (EEIGM) on the 7-8 November 2011 in Nancy, France. This biennial conference organized by the EEIGM is a wonderful opportunity for all scientists involved in the EEIGM programme, in the 'Erasmus Mundus' Advanced Materials Science and Engineering Master programme (AMASE) and the 'Erasmus Mundus' Doctoral Programme in Materials Science and Engineering (DocMASE), to present their research in the various fields of Materials Science and Engineering. This conference is also open to other universities who have strong links with the EEIGM and provides a forum for the exchange of ideas, co-operation and future orientations by means of regular presentations, posters and a round-table discussion. This edition of the conference included a round-table discussion on composite materials within the Interreg IVA project '+Composite'. Following the publication of the proceedings of AMR 2009 in Volume 5 of this journal, it is with great pleasure that we present this selection of articles to the readers of IOP Conference Series: Materials Science and Engineering. Once again it represents the interdisciplinary nature of Materials Science and Engineering, covering basic and applicative research on organic and composite materials, metallic materials and ceramics, and characterization methods. The editors are indebted to all the reviewers for reviewing the papers at very short notice. Special thanks are offered to the sponsors of the conference including EEIGM-Université de Lorraine, AMASE, DocMASE, Grand Nancy, Ville de Nancy, Region Lorraine, Fédération Jacques Villermaux, Conseil Général de Meurthe et Moselle, Casden and '+Composite'. Zoubir Ayadi, David Horwat and Brigitte Jamart

  14. Electric utility acid fuel cell stack technology advancement

    NASA Technical Reports Server (NTRS)

    Congdon, J. V.; Goller, G. J.; Greising, G. J.; Obrien, J. J.; Randall, S. A.; Sandelli, G. J.; Breault, R. D.; Austin, G. W.; Bopse, S.; Coykendall, R. D.

    1984-01-01

    The principal effort under this program was directed at the fuel cell stack technology required to accomplish the initial feasibility demonstrations of increased cell stack operating pressures and temperatures, increased cell active area, incorporation of the ribbed substrate cell configuration at the bove conditions, and the introduction of higher performance electrocatalysts. The program results were successful with the primary accomplishments being: (1) fabrication of 10 sq ft ribbed substrate, cell components including higher performing electrocatalysts; (2) assembly of a 10 sq ft, 30-cell short stack; and (3) initial test of this stack at 120 psia and 405 F. These accomplishments demonstrate the feasibility of fabricating and handling large area cells using materials and processes that are oriented to low cost manufacture. An additional accomplishment under the program was the testing of two 3.7 sq ft short stacks at 12 psia/405 F to 5400 and 4500 hours respectively. These tests demonstrate the durability of the components and the cell stack configuration to a nominal 5000 hours at the higher pressure and temperature condition planned for the next electric utility power plant.

  15. Glass-ceramic materials from electric arc furnace dust.

    PubMed

    Kavouras, P; Kehagias, T; Tsilika, I; Kaimakamis, G; Chrissafis, K; Kokkou, S; Papadopoulos, D; Karakostas, Th

    2007-01-31

    Electric arc furnace dust (EAFD) was vitrified with SiO2, Na2CO3 and CaCO3 powders in an electric furnace at ambient atmosphere. Vitreous products were transformed into glass-ceramic materials by two-stage heat treatment, at temperatures determined by differential thermal analysis. Both vitreous and glass-ceramic materials were chemically stable. Wollastonite (CaSiO3) was separated from the parent matrix as the dominant crystalline phase, verified by X-ray diffraction analysis and energy dispersive spectrometry. Transmission electron microscopy revealed that wollastonite crystallizes mainly in its monoclinic form. Knoop microhardness was measured with the static indentation test method in all initial vitreous products and the microhardness values were in the region of 5.0-5.5 GPa. Devitrification resulted in glass-ceramic materials with microhardness values strongly dependent on the morphology and orientation of the separated crystal phase. PMID:16716504

  16. Concept for the intrinsic dielectric strength of electrical insulation materials

    SciTech Connect

    Cuddihy, E.F.

    1985-04-15

    A concept is described for a possible definition of the intrinsic dielectric strength of insulating materials, which can be considered as a fundamental material property similar to other material properties, such as Young's modulus, index of refraction, and expansion coefficients. The events leading to the recognition of this property are reported, and the property is defined. This intrinsic dielectric strength concept should facilitate interpretation of results from accelerated and/or natural aging programs intended to predict electrical insulation service life of encapsulants in photovoltaic modules. As a practical application, this new concept enabled a possible explanation of the cause of failures in buried high-voltage cables with polyethylene insulation, and a possible explanation of the causes of electrical trees in polyethylene; these also are described.

  17. ANALYSIS ON EFFLUENT WATER QUALITY AND ELECTRICITY CONSUMPTION AFTER INTRODUCING ADVANCED SEWAGE TREATMENT

    NASA Astrophysics Data System (ADS)

    Shiojiri, Yasuo; Maekawa, Shunich

    We analyze effluent water quality and electricity consumption after in troducing advanced treatment in sewage treatment plant. We define 'advanced treatment ratio' as volume of treated water through advanced treatment processes divided by total volume of treated water in plant. Advanced treatment ratio represents degree of introducing advanced treatment. We build two types of equation. One represents relation between effluent water quality and advanced treatment ratio, the other between electricity consumption and advanced treatment ratio. Each equation is fitted by least squares on 808 samples: 8 fiscal years operation data of 101 plants working in Kanagawa, Tokyo, Saitama and Chiba areas, and coefficient of advanced treatment ratio is estimated. The result is as follows. (1) After introducing advanced treatment aimed at nitrogen removal, T-N in effluent water decreases by 51.3% and electricity consum ption increases by 52.2%. (2) After introducing advanced treatment aimed at phosphorus removal, T-P in effluent water decreases by 27.8%. Using the above result, we try prioritizing 71 plants in Tokyo Bay watershed about raising advanced treatment ratio, so that, in total, pollutant in effluent water decreases with minimized increase of electricity consumption.

  18. Analysis of Advanced Thermoelectric Materials and Their Functional Limits

    NASA Technical Reports Server (NTRS)

    Kim, Hyun Jung

    2015-01-01

    The world's demand for energy is increasing dramatically, but the best energy conversion systems operate at approximately 30% efficiency. One way to decrease energy loss is in the recovery of waste heat using thermoelectric (TE) generators. A TE generator is device that generates electricity by exploiting heat flow across a thermal gradient. The efficiency of a TE material for power generation and cooling is determined by the dimensionless Figure of Merit (ZT): ZT = S(exp. 2)sigmaT/?: where S is the Seebeck coefficient, sigma is the electrical conductivity, T is the absolute temperature, and ? is the thermal conductivity. The parameters are not physically independent, but intrinsically coupled since they are a function of the transport properties of electrons. Traditional research on TE materials has focused on synthesizing bulk semiconductor-type materials that have low thermal conductivity and high electrical conductivity affording ZT values of 1. The optimization of the s/? ratio is difficult to achieve using current material formats, as these material constants are complementary. Recent areas of research are focusing on using nanostructural artifacts that introduce specific dislocations and boundary conditions that scatter the phonons. This disrupts the physical link between thermal (phonon) and electrical (electron) transport. The result is that ? is decreased without decreasing s. These material formats give ZT values of up to 2 which represent approximately 18% energy gain from waste heat recovery. The next challenge in developing the next generation of TE materials with superior performance is to tailor the interconnected thermoelectric physical parameters of the material system. In order to approach this problem, the fundamental physics of each parameter S, sigma, and ? need to be physically understood in their context of electron/phonon interaction for the construction of new high ZT thermoelectric devices. Is it possible to overcome the physical limit

  19. Report on sodium compatibility of advanced structural materials.

    SciTech Connect

    Li, M.; Natesan, K.; Momozaki, Y.; Rink, D.L.; Soppet, W.K.; Listwan, J.T.

    2012-07-09

    This report provides an update on the evaluation of sodium compatibility of advanced structural materials. The report is a deliverable (level 3) in FY11 (M3A11AN04030403), under the Work Package A-11AN040304, 'Sodium Compatibility of Advanced Structural Materials' performed by Argonne National Laboratory (ANL), as part of Advanced Structural Materials Program for the Advanced Reactor Concepts. This work package supports the advanced structural materials development by providing corrosion and tensile data from the standpoint of sodium compatibility of advanced structural alloys. The scope of work involves exposure of advanced structural alloys such as G92, mod.9Cr-1Mo (G91) ferritic-martensitic steels and HT-UPS austenitic stainless steels to a flowing sodium environment with controlled impurity concentrations. The exposed specimens are analyzed for their corrosion performance, microstructural changes, and tensile behavior. Previous reports examined the thermodynamic and kinetic factors involved in the purity of liquid sodium coolant for sodium reactor applications as well as the design, fabrication, and construction of a forced convection sodium loop for sodium compatibility studies of advanced materials. This report presents the results on corrosion performance, microstructure, and tensile properties of advanced ferritic-martensitic and austenitic alloys exposed to liquid sodium at 550 C for up to 2700 h and at 650 C for up to 5064 h in the forced convection sodium loop. The oxygen content of sodium was controlled by the cold-trapping method to achieve {approx}1 wppm oxygen level. Four alloys were examined, G92 in the normalized and tempered condition (H1 G92), G92 in the cold-rolled condition (H2 G92), G91 in the normalized and tempered condition, and hot-rolled HT-UPS. G91 was included as a reference to compare with advanced alloy, G92. It was found that all four alloys showed weight loss after sodium exposures at 550 and 650 C. The weight loss of the four

  20. Technology Readiness Levels for Advanced Nuclear Fuels and Materials Development

    SciTech Connect

    Jon Carmack

    2014-01-01

    The Technology Readiness Level (TRL) process is used to quantitatively assess the maturity of a given technology. The TRL process has been developed and successfully used by the Department of Defense (DOD) for development and deployment of new technology and systems for defense applications. In addition, NASA has also successfully used the TRL process to develop and deploy new systems for space applications. Advanced nuclear fuels and materials development is a critical technology needed for closing the nuclear fuel cycle. Because the deployment of a new nuclear fuel forms requires a lengthy and expensive research, development, and demonstration program, applying the TRL concept to the advanced fuel development program is very useful as a management and tracking tool. This report provides definition of the technology readiness level assessment process as defined for use in assessing nuclear fuel technology development for the Advanced Fuel Campaign (AFC).

  1. Advanced Bioinks for 3D Printing: A Materials Science Perspective.

    PubMed

    Chimene, David; Lennox, Kimberly K; Kaunas, Roland R; Gaharwar, Akhilesh K

    2016-06-01

    Advanced bioinks for 3D printing are rationally designed materials intended to improve the functionality of printed scaffolds outside the traditional paradigm of the "biofabrication window". While the biofabrication window paradigm necessitates compromise between suitability for fabrication and ability to accommodate encapsulated cells, recent developments in advanced bioinks have resulted in improved designs for a range of biofabrication platforms without this tradeoff. This has resulted in a new generation of bioinks with high print fidelity, shear-thinning characteristics, and crosslinked scaffolds with high mechanical strength, high cytocompatibility, and the ability to modulate cellular functions. In this review, we describe some of the promising strategies being pursued to achieve these goals, including multimaterial, interpenetrating network, nanocomposite, and supramolecular bioinks. We also provide an overview of current and emerging trends in advanced bioink synthesis and biofabrication, and evaluate the potential applications of these novel biomaterials to clinical use. PMID:27184494

  2. Polymers as advanced materials for desiccant applications, 1988

    SciTech Connect

    Czanderna, A.W.; Neidlinger, H.H.

    1990-09-01

    This report documents work to identify a next-generation, low-cost material with which solar energy or heat from another low-cost energy source can be used for regenerating the water vapor sorption activity of the desiccant. The objective of the work is to determine how the desired sorption performance of advanced desiccant materials can be predicted by understanding the role of the material modifications and material surfaces. The work concentrates on solid materials to be used for desiccant cooling systems and which process water vapor in an atmosphere to produce cooling. The work involved preparing modifications of polystyrene sulfonic acid sodium salt, synthesizing a hydrogel, and evaluating the sorption performances of these and similar commercially available polymeric materials; all materials were studied for their potential application in solid commercial desiccant cooling systems. Background information is also provided on desiccant cooling systems and the role of a desiccant material within such a system, and it includes the use of polymers as desiccant materials. 31 refs., 16 figs., 5 tabs.

  3. Recent Advances in Nuclear Powered Electric Propulsion for Space Exploration

    NASA Technical Reports Server (NTRS)

    Cassady, R. Joseph; Frisbee, Robert H.; Gilland, James H.; Houts, Michael G.; LaPointe, Michael R.; Maresse-Reading, Colleen M.; Oleson, Steven R.; Polk, James E.; Russell, Derrek; Sengupta, Anita

    2007-01-01

    Nuclear and radioisotope powered electric thrusters are being developed as primary in-space propulsion systems for potential future robotic and piloted space missions. Possible applications for high power nuclear electric propulsion include orbit raising and maneuvering of large space platforms, lunar and Mars cargo transport, asteroid rendezvous and sample return, and robotic and piloted planetary missions, while lower power radioisotope electric propulsion could significantly enhance or enable some future robotic deep space science missions. This paper provides an overview of recent U.S. high power electric thruster research programs, describing the operating principles, challenges, and status of each technology. Mission analysis is presented that compares the benefits and performance of each thruster type for high priority NASA missions. The status of space nuclear power systems for high power electric propulsion is presented. The paper concludes with a discussion of power and thruster development strategies for future radioisotope electric propulsion systems,

  4. Corrosion performance of materials for advanced combustion systems

    SciTech Connect

    Natesan, K.; Yanez-Herrero, M.; Fornasieri, C.

    1993-12-01

    Conceptual designs of advanced combustion systems that utilize coal as a feedstock require high-temperature furnaces and heat transfer surfaces capable of operating at more elevated temperatures than those prevalent in current coal-fired power plants. The combination of elevated temperatures and hostile combustion environments necessitates development/application of advanced ceramic materials in these designs. This report characterizes the chemistry of coal-fired combustion environments over the wide temperature range that is of interest in these systems and discusses preliminary experimental results on several materials (alumina, Hexoloy, SiC/SiC, SiC/Si{sub 3}N{sub 4}/Si{sub 3}N{sub 4}, ZIRCONIA, INCONEL 677 and 617) with potential for application in these systems.

  5. Mishap risk control for advanced aerospace/composite materials

    NASA Technical Reports Server (NTRS)

    Olson, John M.

    1994-01-01

    Although advanced aerospace materials and advanced composites provide outstanding performance, they also present several unique post-mishap environmental, safety, and health concerns. The purpose of this paper is to provide information on some of the unique hazards and concerns associated with these materials when damaged by fire, explosion, or high-energy impact. Additionally, recommended procedures and precautions are addressed as they pertain to all phases of a composite aircraft mishap response, including fire-fighting, investigation, recovery, clean-up, and guidelines are general in nature and not application-specific. The goal of this project is to provide factual and realistic information which can be used to develop consistent and effective procedures and policies to minimize the potential environmental, safety, and health impacts of a composite aircraft mishap response effort.

  6. A combinatorial approach to the discovery of advanced materials

    NASA Astrophysics Data System (ADS)

    Sun, Xiao-Dong

    This thesis discusses the application of combinatorial methods to the search of advanced materials. The goal of this research is to develop a "parallel" or "fast sequential" methodology for both the synthesis and characterization of materials with novel electronic, magnetic and optical properties. Our hope is to dramatically accelerate the rate at which materials are generated and studied. We have developed two major combinatorial methodologies to this end. One involves generating thin film materials libraries using a combination of various thin film deposition and masking strategies with multi-layer thin film precursors. The second approach is to generate powder materials libraries with solution precursors delivered with a multi-nozzle inkjet system. The first step in this multistep combinatorial process involves the design and synthesis of high density libraries of diverse materials aimed at exploring a large segment of the compositional space of interest based on our understanding of the physical and structural properties of a particular class of materials. Rapid, sensitive measurements of one or more relevant physical properties of each library member result in the identification of a family of "lead" compositions with a desired property. These compositions are then optimized by continuously varying the stoichiometries of a more focused set of precursors. Materials with the optimal composition are then synthesized in quantities sufficient for detailed characterization of their structural and physical properties. Finally, the information obtained from this process should enhance our predictive ability in subsequent experiments. Combinatorial methods have been successfully used in the synthesis and discovery of materials with novel properties. For example, a class of cobaltite based giant magnetoresistance (GMR) ceramics was discovered; Application of this method to luminescence materials has resulted in the discovery of a few highly efficient tricolor

  7. Silicon as an advanced window material for high power gyrotrons

    SciTech Connect

    Parshin, V.V.; Andreev, B.A.; Gusev, A.V.

    1995-05-01

    The absorptivity of high-purity grades of silicon (Si) and its reduction by subsequent doping procedures are investigated. The dielectric data are given for the wide range of frequencies (30 -330 GHz) and temperatures (30 -330 K) in comparison with the data set for sapphire. The advanced material performance in high power window applications is discussed taking into account both dielectric properties of the optimized silicon grades and thermal conductivity.

  8. ADVANCED HOT SECTION MATERIALS AND COATINGS TEST RIG

    SciTech Connect

    Scott Reome; Dan Davies

    2004-01-01

    The Hyperbaric Advanced Hot Section Materials & Coating Test Rig program initiated this quarter, provides design and implementation of a laboratory rig capable of simulating the hot gas path conditions of coal-gas fired industrial gas turbine engines. The principle activity during this first reporting period were preparing for and conducting a project kick-off meeting, working through plans for the project implementation, and beginning the conceptual design of the test section.

  9. Materials Advances to Enhance Development of Geothermal Power

    SciTech Connect

    Kukacka, Lawrence E.

    1989-03-21

    In order to assure the continued development of geothermal resources, many advances in materials technology are required so that high costs resulting from the severe environments encountered during drilling, well completion and energy extraction can be reduced. These needs will become more acute as higher temperature and chemically aggressive fluids are encountered. High priority needs are for lost circulation control and lightweight well completion materials, and tools such as drill pipe protectors, rotating head seals, blow-out preventers, and downhole drill motors. The lack of suitable hydrolytically stable chemical systems that can bond previously developed elastomers to metal reinforcement is a critical but as yet unaddressed impediment to the development of these tools. In addition, the availability of low cost corrosion and scale-resistant tubular lining materials would greatly enhance transport and energy extraction processes utilizing hypersaline brines. Work to address these materials needs is underway at Brookhaven National Laboratory (BNL), and recent accomplishments are summarized in the paper.

  10. [Advances of poly (ionic liquid) materials in separation science].

    PubMed

    Liu, Cuicui; Guo, Ting; Su, Rina; Gu, Yuchen; Deng, Qiliang

    2015-11-01

    Ionic liquids, as novel ionization reagents, possess beneficial characteristics including good solubility, conductivity, thermal stability, biocompatibility, low volatility and non-flammability. Ionic liquids are attracting a mass of attention of analytical chemists. Poly (ionic liquid) materials have common performances of ionic liquids and polymers, and have been successfully applied in separation science area. In this paper, we discuss the interaction mechanisms between the poly(ionic liquid) materials and analytes including hydrophobic/hydrophilic interactions, hydrogen bond, ion exchange, π-π stacking and electrostatic interactions, and summarize the application advances of the poly(ionic liquid) materials in solid phase extraction, chromatographic separation and capillary electrophoresis. At last, we describe the future prospect of poly(ionic liquid) materials. PMID:26939357

  11. Ultrasonic and radiographic evaluation of advanced aerospace materials: Ceramic composites

    NASA Technical Reports Server (NTRS)

    Generazio, Edward R.

    1990-01-01

    Two conventional nondestructive evaluation techniques were used to evaluate advanced ceramic composite materials. It was shown that neither ultrasonic C-scan nor radiographic imaging can individually provide sufficient data for an accurate nondestructive evaluation. Both ultrasonic C-scan and conventional radiographic imaging are required for preliminary evaluation of these complex systems. The material variations that were identified by these two techniques are porosity, delaminations, bond quality between laminae, fiber alignment, fiber registration, fiber parallelism, and processing density flaws. The degree of bonding between fiber and matrix cannot be determined by either of these methods. An alternative ultrasonic technique, angular power spectrum scanning (APSS) is recommended for quantification of this interfacial bond.

  12. Solar hydrogen and solar electricity using mesoporous materials

    NASA Astrophysics Data System (ADS)

    Mahoney, Luther

    The development of cost-effective materials for effective utilization of solar energy is a major challenge for solving the energy problems that face the world. This thesis work relates to the development of mesoporous materials for solar energy applications in the areas of photocatalytic water splitting and the generation of electricity. Mesoporous materials were employed throughout the studies because of their favorable physico-chemical properties such as high surface areas and large porosities. The first project was related to the use of a cubic periodic mesoporous material, MCM-48. The studies showed that chromium loading directly affected the phase of mesoporous silica formed. Furthermore, within the cubic MCM-48 structure, the loading of polychromate species determined the concentration of solar hydrogen produced. In an effort to determine the potential of mesoporous materials, titanium dioxide was prepared using the Evaporation-Induced Self-Assembly (EISA) synthetic method. The aging period directly determined the amount of various phases of titanium dioxide. This method was extended for the preparation of cobalt doped titanium dioxide for solar simulated hydrogen evolution. In another study, metal doped systems were synthesized using the EISA procedure and rhodamine B (RhB) dye sensitized and metal doped titania mesoporous materials were evaluated for visible light hydrogen evolution. The final study employed various mesoporous titanium dioxide materials for N719 dye sensitized solar cell (DSSC) materials for photovoltaic applications. The materials were extensively characterized using powder X-ray diffraction (XRD), nitrogen physisorption, diffuse reflectance spectroscopy (DRS), UV-Vis spectroscopy, Fourier-Transform-Infrared Spectroscopy (FT-IR), Raman spectroscopy, chemisorption, photoluminescence (PL), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). In addition, photoelectrochemical measurements were completed using

  13. Advanced materials and biochemical processes for geothermal applications

    SciTech Connect

    Kukacka, L.E.; van Rooyen, D.; Premuzic, E.T.

    1987-04-01

    Two Geothermal Technology Division (GTD)-sponsored programs: (1) Geothermal Materials Development, and (2) Advanced Biochemical Processes for Geothermal Brines, are described. In the former, work in the following tasks is in progress: (1) high temperature elastomeric materials for dynamic sealing applications, (2) advanced high temperature (300/sup 0/C) lightweight (1.1 g/cc) well cementing materials, (3) thermally conductive composites for heat exchanger tubing, (4) corrosion rates for metals in brine-contaminated binary plant working fluids, and (5) elastomeric liners for well casing. Methods for the utilization and/or the low cost environmentally acceptable disposal of toxic geothermal residues are being developed in the second program. This work is performed in two tasks. In one, microorganisms that can interact with toxic metals found in geothermal residues to convert them into soluble species for subsequent reinjection back into the reservoir or to concentrate them for removal by conventional processes are being identified. In the second task, process conditions are being defined for the encapsulation of untreated or partially biochemically treated residues in Portland cement-based formulations and the subsequent utilization of the waste fractions in building materials. Both processing methods yield materials which appear to meet disposal criteria for non-toxic solid waste, and their technical and economic feasibilities have been established.

  14. Sol-gel Technology and Advanced Electrochemical Energy Storage Materials

    NASA Technical Reports Server (NTRS)

    Chu, Chung-tse; Zheng, Haixing

    1996-01-01

    Advanced materials play an important role in the development of electrochemical energy devices such as batteries, fuel cells, and electrochemical capacitors. The sol-gel process is a versatile solution for use in the fabrication of ceramic materials with tailored stoichiometry, microstructure, and properties. This processing technique is particularly useful in producing porous materials with high surface area and low density, two of the most desirable characteristics for electrode materials. In addition,the porous surface of gels can be modified chemically to create tailored surface properties, and inorganic/organic micro-composites can be prepared for improved material performance device fabrication. Applications of several sol-gel derived electrode materials in different energy storage devices are illustrated in this paper. V2O5 gels are shown to be a promising cathode material for solid state lithium batteries. Carbon aerogels, amorphous RuO2 gels and sol-gel derived hafnium compounds have been studied as electrode materials for high energy density and high power density electrochemical capacitors.

  15. Effect of new cleaning solvents on electrical insulation materials

    SciTech Connect

    Lamarre, L.; Amyot, N.; Durand, M.; Laverdure, C.

    1996-12-31

    Trichloroethane which was often used to clean high voltage cables (during installation of joints or terminations), various accessories, generators and motors, now has to be replaced by friendlier solvents to protect the ozone layer. Among the new solvents considered, di-chloro-fluoro ethanes prove to be the best candidates; terpenes offered a cheaper alternative for some applications. A set of various physical, chemical and electrical tests was designed to assess compatibility and preservation of long term electrical performance of the insulation materials exposed to the cleaning solvent. Physical testing includes swelling, decoloration and elongation at break measurements. Chemical tests includes volatility, residue analysis; attention was paid to the flash point. Electrical performance was checked using tan {delta}, resistance to breakdown and tracking tests.

  16. Advanced thermoplastic materials for district heating piping systems

    SciTech Connect

    Raske, D.T.; Karvelas, D.E.

    1988-04-01

    The work described in this report represents research conducted in the first year of a three-year program to assess, characterize, and design thermoplastic piping for use in elevated-temperature district heating (DH) systems. The present report describes the results of a program to assess the potential usefulness of advanced thermoplastics as piping materials for use in DH systems. This includes the review of design rules for thermoplastic materials used as pipes, a survey of candidate materials and available mechanical properties data, and mechanical properties testing to obtain baseline data on a candidate thermoplastic material extruded as pipe. The candidate material studied in this phase of the research was a polyetherimide resin, Ultem 1000, which has a UL continuous service temperature rating of 338/degree/F (170/degree/C). The results of experiments to determine the mechanical properties between 68 and 350/degree/F (20 and 177/degree/C) were used to establish preliminary design values for this material. Because these prototypic pipes were extruded under less than optimal conditions, the mechanical properties obtained are inferior to those expected from typical production pipes. Nevertheless, the present material in the form of 2-in. SDR 11 pipe (2.375-in. O. D. by 0.216-in. wall) would have a saturated water design pressure rating of /approximately/34 psig at 280/degree/F. 16 refs., 6 figs., 8 tabs.

  17. Advanced composite structural concepts and materials technologies for primary aircraft structures: Advanced material concepts

    NASA Technical Reports Server (NTRS)

    Lau, Kreisler S. Y.; Landis, Abraham L.; Chow, Andrea W.; Hamlin, Richard D.

    1993-01-01

    To achieve acceptable performance and long-term durability at elevated temperatures (350 to 600 F) for high-speed transport systems, further improvements of the high-performance matrix materials will be necessary to achieve very long-term (60,000-120,000 service hours) retention of mechanical properties and damage tolerance. This report emphasizes isoimide modification as a complementary technique to semi-interpenetrating polymer networks (SIPN's) to achieve greater processibility, better curing dynamics, and possibly enhanced thermo-mechanical properties in composites. A key result is the demonstration of enhanced processibility of isoimide-modified linear and thermo-setting polyimide systems.

  18. Area Reports. Advanced materials and devices research area. Silicon materials research task, and advanced silicon sheet task

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The objectives of the Silicon Materials Task and the Advanced Silicon Sheet Task are to identify the critical technical barriers to low-cost silicon purification and sheet growth that must be overcome to produce a PV cell substrate material at a price consistent with Flat-plate Solar Array (FSA) Project objectives and to overcome these barriers by performing and supporting appropriate R&D. Progress reports are given on silicon refinement using silane, a chemical vapor transport process for purifying metallurgical grade silicon, silicon particle growth research, and modeling of silane pyrolysis in fluidized-bed reactors.

  19. Materials Advances for Next-Generation Ingestible Electronic Medical Devices.

    PubMed

    Bettinger, Christopher J

    2015-10-01

    Electronic medical implants have collectively transformed the diagnosis and treatment of many diseases, but have many inherent limitations. Electronic implants require invasive surgeries, operate in challenging microenvironments, and are susceptible to bacterial infection and persistent inflammation. Novel materials and nonconventional device fabrication strategies may revolutionize the way electronic devices are integrated with the body. Ingestible electronic devices offer many advantages compared with implantable counterparts that may improve the diagnosis and treatment of pathologies ranging from gastrointestinal infections to diabetes. This review summarizes current technologies and highlights recent materials advances. Specific focus is dedicated to next-generation materials for packaging, circuit design, and on-board power supplies that are benign, nontoxic, and even biodegradable. Future challenges and opportunities are also highlighted. PMID:26403162

  20. Testing of Alternative Materials for Advanced Suit Bladders

    NASA Technical Reports Server (NTRS)

    Bue, Grant; Orndoff, Evelyne; Makinen, Janice; Tang, Henry

    2011-01-01

    Several candidate advanced pressure bladder membrane materials have been developed for NASA Johnson Space Center by DSM Biomedical for selective permeability of carbon dioxide and water vapor. These materials were elasthane and two other formulations of thermoplastic polyether polyurethane. Each material was tested in two thicknesses for permeability to carbon dioxide, oxygen and water vapor. Although oxygen leaks through the suit bladder would amount to only about 60 cc/hr in a full size suit, significant amounts of carbon dioxide would not be rejected by the system to justify its use. While the ratio of carbon dioxide to oxygen permeability is about 48 to 1, this is offset by the small partial pressure of carbon dioxide in acceptable breathing atmospheres of the suit. Humidity management remains a possible use of the membranes depending on the degree to which the water permeability is inhibited by cations in the sweat. Tests are underway to explore cation fouling from sweat.

  1. Development of processing techniques for advanced thermal protection materials

    NASA Technical Reports Server (NTRS)

    Selvaduray, Guna S.

    1994-01-01

    The effort, which was focused on the research and development of advanced materials for use in Thermal Protection Systems (TPS), has involved chemical and physical testing of refractory ceramic tiles, fabrics, threads and fibers. This testing has included determination of the optical properties, thermal shock resistance, high temperature dimensional stability, and tolerance to environmental stresses. Materials have also been tested in the Arc Jet 2 x 9 Turbulent Duct Facility (TDF), the 1 atmosphere Radiant Heat Cycler, and the Mini-Wind Tunnel Facility (MWTF). A significant part of the effort hitherto has gone towards modifying and upgrading the test facilities so that meaningful tests can be carried out. Another important effort during this period has been the creation of a materials database. Computer systems administration and support have also been provided. These are described in greater detail below.

  2. Test model designs for advanced refractory ceramic materials

    NASA Technical Reports Server (NTRS)

    Tran, Huy Kim

    1993-01-01

    The next generation of space vehicles will be subjected to severe aerothermal loads and will require an improved thermal protection system (TPS) and other advanced vehicle components. In order to ensure the satisfactory performance system (TPS) and other advanced vehicle materials and components, testing is to be performed in environments similar to space flight. The design and fabrication of the test models should be fairly simple but still accomplish test objectives. In the Advanced Refractory Ceramic Materials test series, the models and model holders will need to withstand the required heat fluxes of 340 to 817 W/sq cm or surface temperatures in the range of 2700 K to 3000 K. The model holders should provide one dimensional (1-D) heat transfer to the samples and the appropriate flow field without compromising the primary test objectives. The optical properties such as the effective emissivity, catalytic efficiency coefficients, thermal properties, and mass loss measurements are also taken into consideration in the design process. Therefore, it is the intent of this paper to demonstrate the design schemes for different models and model holders that would accommodate these test requirements and ensure the safe operation in a typical arc jet facility.

  3. Review on advanced composite materials boring mechanism and tools

    NASA Astrophysics Data System (ADS)

    Shi, Runping; Wang, Chengyong

    2010-12-01

    With the rapid development of aviation and aerospace manufacturing technology, advanced composite materials represented by carbon fibre reinforced plastics (CFRP) and super hybrid composites (fibre/metal plates) are more and more widely applied. The fibres are mainly carbon fibre, boron fibre, Aramid fiber and Sic fibre. The matrixes are resin matrix, metal matrix and ceramic matrix. Advanced composite materials have higher specific strength and higher specific modulus than glass fibre reinforced resin composites of the 1st generation. They are widely used in aviation and aerospace industry due to their high specific strength, high specific modulus, excellent ductility, anticorrosion, heat-insulation, sound-insulation, shock absorption and high&low temperature resistance. They are used for radomes, inlets, airfoils(fuel tank included), flap, aileron, vertical tail, horizontal tail, air brake, skin, baseboards and tails, etc. Its hardness is up to 62~65HRC. The holes are greatly affected by the fibre laminates direction of carbon fibre reinforced composite material due to its anisotropy when drilling in unidirectional laminates. There are burrs, splits at the exit because of stress concentration. Besides there is delamination and the hole is prone to be smaller. Burrs are caused by poor sharpness of cutting edge, delamination, tearing, splitting are caused by the great stress caused by high thrust force. Poorer sharpness of cutting edge leads to lower cutting performance and higher drilling force at the same time. The present research focuses on the interrelation between rotation speed, feed, drill's geometry, drill life, cutting mode, tools material etc. and thrust force. At the same time, holes quantity and holes making difficulty of composites have also increased. It requires high performance drills which won't bring out defects and have long tool life. It has become a trend to develop super hard material tools and tools with special geometry for drilling

  4. Review on advanced composite materials boring mechanism and tools

    NASA Astrophysics Data System (ADS)

    Shi, Runping; Wang, Chengyong

    2011-05-01

    With the rapid development of aviation and aerospace manufacturing technology, advanced composite materials represented by carbon fibre reinforced plastics (CFRP) and super hybrid composites (fibre/metal plates) are more and more widely applied. The fibres are mainly carbon fibre, boron fibre, Aramid fiber and Sic fibre. The matrixes are resin matrix, metal matrix and ceramic matrix. Advanced composite materials have higher specific strength and higher specific modulus than glass fibre reinforced resin composites of the 1st generation. They are widely used in aviation and aerospace industry due to their high specific strength, high specific modulus, excellent ductility, anticorrosion, heat-insulation, sound-insulation, shock absorption and high&low temperature resistance. They are used for radomes, inlets, airfoils(fuel tank included), flap, aileron, vertical tail, horizontal tail, air brake, skin, baseboards and tails, etc. Its hardness is up to 62~65HRC. The holes are greatly affected by the fibre laminates direction of carbon fibre reinforced composite material due to its anisotropy when drilling in unidirectional laminates. There are burrs, splits at the exit because of stress concentration. Besides there is delamination and the hole is prone to be smaller. Burrs are caused by poor sharpness of cutting edge, delamination, tearing, splitting are caused by the great stress caused by high thrust force. Poorer sharpness of cutting edge leads to lower cutting performance and higher drilling force at the same time. The present research focuses on the interrelation between rotation speed, feed, drill's geometry, drill life, cutting mode, tools material etc. and thrust force. At the same time, holes quantity and holes making difficulty of composites have also increased. It requires high performance drills which won't bring out defects and have long tool life. It has become a trend to develop super hard material tools and tools with special geometry for drilling

  5. A manufacturing database of advanced materials used in spacecraft structures

    NASA Technical Reports Server (NTRS)

    Bao, Han P.

    1994-01-01

    Cost savings opportunities over the life cycle of a product are highest in the early exploratory phase when different design alternatives are evaluated not only for their performance characteristics but also their methods of fabrication which really control the ultimate manufacturing costs of the product. In the past, Design-To-Cost methodologies for spacecraft design concentrated on the sizing and weight issues more than anything else at the early so-called 'Vehicle Level' (Ref: DOD/NASA Advanced Composites Design Guide). Given the impact of manufacturing cost, the objective of this study is to identify the principal cost drivers for each materials technology and propose a quantitative approach to incorporating these cost drivers into the family of optimization tools used by the Vehicle Analysis Branch of NASA LaRC to assess various conceptual vehicle designs. The advanced materials being considered include aluminum-lithium alloys, thermoplastic graphite-polyether etherketone composites, graphite-bismaleimide composites, graphite- polyimide composites, and carbon-carbon composites. Two conventional materials are added to the study to serve as baseline materials against which the other materials are compared. These two conventional materials are aircraft aluminum alloys series 2000 and series 7000, and graphite-epoxy composites T-300/934. The following information is available in the database. For each material type, the mechanical, physical, thermal, and environmental properties are first listed. Next the principal manufacturing processes are described. Whenever possible, guidelines for optimum processing conditions for specific applications are provided. Finally, six categories of cost drivers are discussed. They include, design features affecting processing, tooling, materials, fabrication, joining/assembly, and quality assurance issues. It should be emphasized that this database is not an exhaustive database. Its primary use is to make the vehicle designer

  6. Advanced two-photon photolithography for patterning of transparent, electrically conductive ionic liquid-polymer nanostructures

    NASA Astrophysics Data System (ADS)

    Bakhtina, Natalia A.; MacKinnon, Neil; Korvink, Jan G.

    2016-04-01

    A key challenge in micro- and nanotechnology is the direct patterning of functional structures. For example, it is highly desirable to possess the ability to create three-dimensional (3D), conductive, and optically transparent structures. Efforts in this direction have, to date, yielded less than optimal results since the polymer composites had low optical transparency over the visible range, were only slightly conductive, or incompatible with high resolution structuring. We have previously presented the novel cross-linkable, conductive, highly transparent composite material based on a photoresist (IP-L 780, OrmoComp, or SU-8) and the ionic liquid 1-butyl-3-methylimidazolium dicyanamide. Material patterning by conventional and two-photon photolithography has been demonstrated as proof-of-concept. Aiming to increase the resolution and to extend the spectrum of exciting applications we continued our research into identifying new ionic liquid - polymer composites. In this paper, we report the precise 3D single-step structuring of optically transparent and electrically conductive ionic liquid - polymer nanostructures with the highest spatial resolution (down to 150 nm) achieved to date. This was achieved via the development of novel cross-linkable composite based on the photoresist IP-G 780 and the ionic liquid 1-butyl-3-methylimidazolium dicyanamide. The successful combination of the developed material with the advanced direct laser writing technique enabled the time- and cost-saving direct manufacturing of transparent, electrically conductive components. We believe that the excellent characteristics of the structured material will open a wider range of exciting applications.

  7. Advanced Materials Development Program: Ceramic Technology for Advanced Heat Engines program plan, 1983--1993

    SciTech Connect

    Not Available

    1990-07-01

    The purpose of the Ceramic Technology for Advanced Heat Engines (CTAHE) Project is the development of an industrial technology base capable of providing reliable and cost-effective high temperature ceramic components for application in advanced heat engines. There is a deliberate emphasis on industrial'' in the purpose statement. The project is intended to support the US ceramic and engine industries by providing the needed ceramic materials technology. The heat engine programs have goals of component development and proof-of-concept. The CTAHE Project is aimed at developing generic basic ceramic technology and does not involve specific engine designs and components. The materials research and development efforts in the CTAHE Project are focused on the needs and general requirements of the advanced gas turbine and low heat rejection diesel engines. The CTAHE Project supports the DOE Office of Transportation Systems' heat engine programs, Advanced Turbine Technology Applications (ATTAP) and Heavy Duty Transport (HDT) by providing the basic technology required for development of reliable and cost-effective ceramic components. The heat engine programs provide the iterative component design, fabrication, and test development logic. 103 refs., 18 figs., 11 tabs.

  8. Supramolecular polymer adhesives: advanced materials inspired by nature.

    PubMed

    Heinzmann, Christian; Weder, Christoph; de Espinosa, Lucas Montero

    2016-01-21

    Due to their dynamic, stimuli-responsive nature, non-covalent interactions represent versatile design elements that can be found in nature in many molecular processes or materials, where adaptive behavior or reversible connectivity is required. Examples include molecular recognition processes, which trigger biological responses or cell-adhesion to surfaces, and a broad range of animal secreted adhesives with environment-dependent properties. Such advanced functionalities have inspired researchers to employ similar design approaches for the development of synthetic polymers with stimuli-responsive properties. The utilization of non-covalent interactions for the design of adhesives with advanced functionalities such as stimuli responsiveness, bonding and debonding on demand capability, surface selectivity or recyclability is a rapidly emerging subset of this field, which is summarized in this review. PMID:26203784

  9. Advanced nanostructured carbon materials for electrical double layer capacitors

    NASA Astrophysics Data System (ADS)

    Jänes, A.; Kurig, H.; Thomberg, T.; Lust, E.

    2007-12-01

    Thermodynamical and electrochemical characteristics for the non-aqueous electrolyte mid nanostructured carbide-derived carbon (CDC), activated carbon cloth (ACC) or commercial activated nanoporous carbon RP-20 (from Kuraray Chemical Co.) interface have been established by XRD, Raman spectroscopy, BET, cyclic voltammetry and electrochemical impedance spectroscopy. The gas adsorption measurement data have been used for the obtaining the specific surface area, pore size distribution, nanopore volume and other characteristics, dependent on the nanostructured carbon used (nanopores are pores in the range of 2 nm and below — i.e. micropores according to IUPAC classification).

  10. (Advanced materials, robotics, and advanced computers for use in nuclear power plants)

    SciTech Connect

    White, J.D.

    1989-11-17

    The aim of the IAEA Technical Committee Workshop was to provide an opportunity to exchange information on the status of advances in technologies such as improved materials, robotics, and advanced computers already used or expected to be used in the design of nuclear power plants, and to review possible applications of advanced technologies in future reactor designs. Papers were given in these areas by Belgium, France, Mexico, Canada, Russia, India, and the United States. Notably absent from this meeting were Japan, Germany, Italy, Spain, the United Kingdom, and the Scandinavian countries -- all of whom are working in the areas of interest to this meeting. Most of the workshop discussion, however, was focused on advanced controls (including human-machine interface and software development and testing) and electronic descriptions of power plants. Verification and validation of design was also a topic of considerable discussion. The traveler was surprised at the progress made in 3-D electronic images of nuclear power plants and automatic updating of these images to reflect as-built conditions. Canadian plants and one Mexican plant have used photogrammetry to update electronic drawings automatically. The Canadians also have started attaching other electronic data bases to the electronic drawings. These data bases include parts information and maintenance work. The traveler observed that the Advanced Controls Program is better balanced and more forward looking than other nuclear controls R D activities described. The French participants made this observation in the meeting and expressed interest in collaborative work in this area.

  11. Materials Science and Materials Chemistry for Large Scale Electrochemical Energy Storage: From Transportation to Electrical Grid

    SciTech Connect

    Liu, Jun; Zhang, Jiguang; Yang, Zhenguo; Lemmon, John P.; Imhoff, Carl H.; Graff, Gordon L.; Li, Liyu; Hu, Jian Z.; Wang, Chong M.; Xiao, Jie; Xia, Guanguang; Viswanathan, Vilayanur V.; Baskaran, Suresh; Sprenkle, Vincent L.; Li, Xiaolin; Shao, Yuyan; Schwenzer, Birgit

    2013-02-15

    Large-scale electrical energy storage has become more important than ever for reducing fossil energy consumption in transportation and for the widespread deployment of intermittent renewable energy in electric grid. However, significant challenges exist for its applications. Here, the status and challenges are reviewed from the perspective of materials science and materials chemistry in electrochemical energy storage technologies, such as Li-ion batteries, sodium (sulfur and metal halide) batteries, Pb-acid battery, redox flow batteries, and supercapacitors. Perspectives and approaches are introduced for emerging battery designs and new chemistry combinations to reduce the cost of energy storage devices.

  12. Four advances in carbon-carbon materials technology

    NASA Technical Reports Server (NTRS)

    Maahs, Howard G.; Vaughn, Wallace L.; Kowbel, Witold

    1994-01-01

    Carbon-carbon composites are a specialty class of materials having many unique properties making these composites attractive for a variety of demanding engineering applications. Chief among these properties are exceptional retention of mechanical properties at temperatures as high as 4000 F, excellent creep resistance, and low density (1.6 to 1.8 g/cu cm). Although carbon-carbon composites are currently in service in a variety of applications, much development work remains to be accomplished before these materials can be considered to be fully mature, realizing their full potential. Four recent technology advances holding particular promise for overcoming current barriers to the wide-spread commercialization of carbon-carbon composites are described. These advances are: markedly improved interlaminar strengths (more than doubled) of two dimensional composites achieved by whiskerization of the fabric reinforcing plies, simultaneously improved oxidation resistance and mechanical properties achieved by the incorporation of matrix-phase oxidation inhibitors based on carborane chemistry, improved oxidation resistance achieved by compositionally graded oxidation protective coatings, and markedly reduced processing times (hours as opposed to weeks or months) accomplished through a novel process of carbon infiltration and coatings deposition based on the use of liquid-phase precursor materials.

  13. 77 FR 56241 - Notice of Withdrawal of Final Design Approval; Westinghouse Electric Company; Advanced Passive 1000

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-12

    ... COMMISSION Notice of Withdrawal of Final Design Approval; Westinghouse Electric Company; Advanced Passive 1000 By letter dated December 10, 2010, Westinghouse Electric Company (WEC) requested that the U.S... initial certification of the four current DCRs was to request that the FDA holder update the Final...

  14. Nanoscale Characterization of Mock Explosive Materials Using Advanced Atomic Force Microscopy Methods

    NASA Astrophysics Data System (ADS)

    Xu, Xin; Mares, Jesus; Groven, Lori J.; Son, Steven F.; Reifenberger, Ronald G.; Raman, Arvind

    2015-01-01

    Most explosives are micro- and nanoscale composite material systems consisting of energetic crystals, amorphous particles, binders, and additives whose response to mechanical, thermal, or electromagnetic insults is often controlled by submicrometer-scale heterogeneities and interfaces. Several advanced dynamic atomic force microscopy (AFM) techniques, including phase imaging, force volume mode, and Kelvin probe force microscopy with resonance enhancement for dielectric property mapping, have been used to map the local physical properties of mock explosive materials systems, allowing the identification of submicrometer heterogeneities in electrical and mechanical properties that could lead to the formation of hotspots under electromagnetic or mechanical stimuli. The physical interpretation of the property maps and the methods of image formation are presented. Possible interpretations of the results and future applications to energetic material systems are also discussed.

  15. Electrical Characterizations of Lightning Strike Protection Techniques for Composite Materials

    NASA Technical Reports Server (NTRS)

    Szatkowski, George N.; Nguyen, Truong X.; Koppen, Sandra V.; Ely, Jay J.; Mielnik, John J.

    2009-01-01

    The growing application of composite materials in commercial aircraft manufacturing has significantly increased the risk of aircraft damage from lightning strikes. Composite aircraft designs require new mitigation strategies and engineering practices to maintain the same level of safety and protection as achieved by conductive aluminum skinned aircraft. Researchers working under the NASA Aviation Safety Program s Integrated Vehicle Health Management (IVHM) Project are investigating lightning damage on composite materials to support the development of new mitigation, diagnosis & prognosis techniques to overcome the increased challenges associated with lightning protection on composite aircraft. This paper provides an overview of the electrical characterizations being performed to support IVHM lightning damage diagnosis research on composite materials at the NASA Langley Research Center.

  16. Amorphous and Nanocomposite Materials for Energy-Efficient Electric Motors

    NASA Astrophysics Data System (ADS)

    Silveyra, Josefina M.; Xu, Patricia; Keylin, Vladimir; DeGeorge, Vincent; Leary, Alex; McHenry, Michael E.

    2016-01-01

    We explore amorphous soft-magnetic alloys as candidates for electric motor applications. The Co-rich system combines the benefits of low hysteretic and eddy-current losses while exhibiting negligible magnetostriction and robust mechanical properties. The amorphous precursors can be devitrified to form nanocomposite magnets. The superior characteristics of these materials offer the advantages of ease of handling in the manufacturing processing and low iron losses during motor operation. Co-rich amorphous ribbons were laser-cut to build a stator for a small demonstrator permanent-magnet machine. The motor was tested up to ~30,000 rpm. Finite-element analyses proved that the iron losses of the Co-rich amorphous stator were ~80% smaller than for a Si steel stator in the same motor, at 18,000 rpm (equivalent to an electric frequency of 2.1 kHz). These low-loss soft magnets have great potential for application in highly efficient high-speed electric machines, leading to size reduction as well as reduction or replacement of rare earths in permanent-magnet motors. More studies evaluating further processing techniques for amorphous and nanocomposite materials are needed.

  17. Materials and Component Development for Advanced Turbine Systems

    SciTech Connect

    Alvin, M A; Pettit, F; Meier, G H; Yanar, M; Helminiak, M; Chyu, M; Siw, S; Slaughter, W S; Karaivanov, V; Kang, B S; Feng, C; Tannebaum, J M; Chen, R; Zhang, B; Fu, T; Richards, G A; Sidwell, T G; Straub, D; Casleton, K H; Dogan, O M

    2008-07-01

    Hydrogen-fired and oxy-fueled land-based gas turbines currently target inlet operating temperatures of ~1425-1760°C (~2600-3200°F). In view of natural gas or syngas-fired engines, advancements in both materials, as well as aerothermal cooling configurations are anticipated prior to commercial operation. This paper reviews recent technical accomplishments resulting from NETL’s collaborative research efforts with the University of Pittsburgh and West Virginia University for future land-based gas turbine applications.

  18. Space Power Architectures for NASA Missions: The Applicability and Benefits of Advanced Power and Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Hoffman, David J.

    2001-01-01

    The relative importance of electrical power systems as compared with other spacecraft bus systems is examined. The quantified benefits of advanced space power architectures for NASA Earth Science, Space Science, and Human Exploration and Development of Space (HEDS) missions is then presented. Advanced space power technologies highlighted include high specific power solar arrays, regenerative fuel cells, Stirling radioisotope power sources, flywheel energy storage and attitude control, lithium ion polymer energy storage and advanced power management and distribution.

  19. Microstructural and mechanical characterization of laser deposited advanced materials

    NASA Astrophysics Data System (ADS)

    Sistla, Harihar Rakshit

    Additive manufacturing in the form of laser deposition is a unique way to manufacture near net shape metallic components from advanced materials. Rapid solidification facilitates the extension of solid solubility, compositional flexibility and decrease in micro-segregation in the melt among other advantages. The current work investigates the employment of laser deposition to fabricate the following: 1. Functionally gradient materials: This allows grading dissimilar materials compositionally to tailor specific properties of both these materials into a single component. Specific compositions of the candidate materials (SS 316, Inconel 625 and Ti64) were blended and deposited to study the brittle intermetallics reported in these systems. 2. High entropy alloys: These are multi- component alloys with equiatomic compositions of 5 or more elements. The ratio of Al to Ni was decreased to observe the transition of solid solution from a BCC to an FCC crystal structure in the AlFeCoCrNi system. 3. Structurally amorphous alloys: Zr-based metallic glasses have been reported to have high glass forming ability. These alloys have been laser deposited so as to rapidly cool them from the melt into an amorphous state. Microstructural analysis and X-ray diffraction were used to study the phase formation, and hardness was measured to estimate the mechanical properties.

  20. Advanced Test Reactor National Scientific User Facility: Addressing advanced nuclear materials research

    SciTech Connect

    John Jackson; Todd Allen; Frances Marshall; Jim Cole

    2013-03-01

    The Advanced Test Reactor National Scientific User Facility (ATR NSUF), based at the Idaho National Laboratory in the United States, is supporting Department of Energy and industry research efforts to ensure the properties of materials in light water reactors are well understood. The ATR NSUF is providing this support through three main efforts: establishing unique infrastructure necessary to conduct research on highly radioactive materials, conducting research in conjunction with industry partners on life extension relevant topics, and providing training courses to encourage more U.S. researchers to understand and address LWR materials issues. In 2010 and 2011, several advanced instruments with capability focused on resolving nuclear material performance issues through analysis on the micro (10-6 m) to atomic (10-10 m) scales were installed primarily at the Center for Advanced Energy Studies (CAES) in Idaho Falls, Idaho. These instruments included a local electrode atom probe (LEAP), a field-emission gun scanning transmission electron microscope (FEG-STEM), a focused ion beam (FIB) system, a Raman spectrometer, and an nanoindentor/atomic force microscope. Ongoing capability enhancements intended to support industry efforts include completion of two shielded, irradiation assisted stress corrosion cracking (IASCC) test loops, the first of which will come online in early calendar year 2013, a pressurized and controlled chemistry water loop for the ATR center flux trap, and a dedicated facility intended to house post irradiation examination equipment. In addition to capability enhancements at the main site in Idaho, the ATR NSUF also welcomed two new partner facilities in 2011 and two new partner facilities in 2012; the Oak Ridge National Laboratory, High Flux Isotope Reactor (HFIR) and associated hot cells and the University California Berkeley capabilities in irradiated materials analysis were added in 2011. In 2012, Purdue University’s Interaction of Materials

  1. Liberalization of the Spanish electricity sector: An advanced model

    SciTech Connect

    Unda, J.I.

    1998-06-01

    Spain`s electricity industry is being restructured to provide a competitive generation market, a regulated, open access transmission and distribution system, and phased-in customer choice. But while the reform is radical in its objectives, it will be gradual in its implementation. This article briefly describes the current state of affairs within the Spanish electricity sector and details the reform plans set out in the act, focusing on the adopted institutional design and the established transition period. It also offers an overview of the role that the regulatory authority will play throughout the process.

  2. Advances in materials and current collecting networks for AMTEC electrodes

    NASA Technical Reports Server (NTRS)

    Ryan, M. A.; Jeffries-Nakamura, B.; Williams, R. M.; Underwood, M. L.; O'Connor, D.; Kikkert, S.

    1992-01-01

    Electrode materials for the Alkali Metal Thermal to Electric Converter (AMTEC) play a significant role in the efficiency of the device. RhW and PtW alloys have been studied to determine the best performing material. While RhW electrodes typically have power densities somewhat lower than PtW electrodes, PtW performance is strongly influenced by the Pt/W ratio. The best performing Pt/W ratio is about 3.4. RhW electrodes sinter more slowly than PtW and are predicted to have operating lifetimes up to 40 years; PtW electrodes are predicted to have lifetimes up to 7 years. Interaction with the current collection network can significantly decrease lifetime by inducing metal migration and segregation and by accelerating the sintering rate.

  3. Correlation of electrical reactor cable failure with materials degradation

    SciTech Connect

    Stuetzer, O.M.

    1986-03-01

    Complete circuit failure (shortout) of electrical cables typically used in nuclear power plant containments is investigated. Failure modes are correlated with the mechanical deterioration of the elastomeric cable materials. It is found that for normal reactor operation, electrical cables are reliable and safe over very long periods. During high temperature excursions, however, cables pulled across corners under high stress may short out due to conductor creep. Severe cracking will occur in short times during high temperatures (>150/sup 0/C) and in times of the order of years at elevated temperatures (100/sup 0/C to 140/sup 0/C). A theoretical treatment of stress distribution responsible for creep and for cracking by J.E. Reaugh of Science Applications, Inc. is contained in the Appendix. 29 refs., 32 figs.

  4. Mesostructured Composite Materials with Electrically Tunable Upconverting Properties.

    PubMed

    Mundoor, Haridas; Smalyukh, Ivan I

    2015-11-01

    A promising approach of designing mesostructured materials with novel physical behavior is to combine unique optical and electronic properties of solid nanoparticles with long-range ordering and facile response of soft matter to weak external stimuli. Here, orientationally ordered nematic liquid crystalline dispersions of rod-like upconversion nanoparticles are designed, practically realized, and characterized. Boundary conditions on particle surfaces, defined through surface functionalization, promote spontaneous unidirectional self-alignment of the dispersed rod-like nanoparticles, mechanically coupled to the molecular ordering direction of the thermotropic nematic liquid crystal host. As host is electrically switched at low voltages ≈ 1 V, nanorods rotate, yielding tunable upconversion and polarized luminescence properties of the composite. Spectral and polarization dependencies are characterized and explained through invoking models of electrical switching of liquid crystals and upconversion dependence on crystalline matrices of nanorods, and their potential practical uses are discussed. PMID:26332163

  5. Development of Tailorable Electrically Conductive Thermal Control Material Systems

    NASA Technical Reports Server (NTRS)

    Deshpande, M. S.; Harada, Y.

    1998-01-01

    The optical characteristics of surfaces on spacecraft are fundamental parameters in controlling its temperature. Passive thermal control coatings with designed solar absorptance and infrared emittance properties have been developed and been in use for some time. In this total space environment, the coating must be stable and maintain its desired optical properties for the course of the mission lifetime. The mission lifetimes are increasing and in our quest to save weight, newer substrates are being integrated which limit electrical grounding schemes. All of this has already added to the existing concerns about spacecraft charging and related spacecraft failures or operational failures. The concern is even greater for thermal control surfaces that are very large. One way of alleviating such concerns is to design new thermal control material systems (TCMS) that can help to mitigate charging via providing charge leakage paths. The object of this program was to develop two types of passive electrically conductive TCMS.

  6. Evaluation of an electric field sensor for nondestructive material inspection

    NASA Astrophysics Data System (ADS)

    Kalyanasundaram, Kayatri; Arunachalam, Kavitha

    2013-01-01

    An electric field sensor is fabricated on a 125 micron thick flexible dielectric substrate for electromagnetic (EM) nondestructive material inspection at 915 MHz. The sensor consists of an electrically short dipole antenna and a radio frequency (RF) diode detector connected to a pair of high impedance screen printed carbon lines. The DC component of the rectified diode voltage conveyed across the high impedance lines is measured using a data acquisition circuit. Sensor measurements are validated with simulated data for a conformal patch antenna operating at 915 MHz. Sensor performance for EM nondestructive testing (NDT) is evaluated using phantom defects in low loss dielectric slabs. Preliminary results indicate sensor utility for EM NDT and support further testing on realistic defects.

  7. Cost/benefit studies of advanced materials technologies for future aircraft turbine engines: Materials for advanced turbine engines

    NASA Technical Reports Server (NTRS)

    Stearns, M.; Wilbers, L.

    1982-01-01

    Cost benefit studies were conducted on six advanced materials and processes technologies applicable to commercial engines planned for production in the 1985 to 1990 time frame. These technologies consisted of thermal barrier coatings for combustor and high pressure turbine airfoils, directionally solidified eutectic high pressure turbine blades, (both cast and fabricated), and mixers, tail cones, and piping made of titanium-aluminum alloys. A fabricated titanium fan blisk, an advanced turbine disk alloy with improved low cycle fatigue life, and a long-life high pressure turbine blade abrasive tip and ceramic shroud system were also analyzed. Technologies showing considerable promise as to benefits, low development costs, and high probability of success were thermal barrier coating, directionally solidified eutectic turbine blades, and abrasive-tip blades/ceramic-shroud turbine systems.

  8. Advanced Hot Section Materials and Coatings Test Rig

    SciTech Connect

    Dan Davis

    2006-09-30

    Phase I of the Hyperbaric Advanced Hot Section Materials & Coating Test Rig Program has been successfully completed. Florida Turbine Technologies has designed and planned the implementation of a laboratory rig capable of simulating the hot gas path conditions of coal gas fired industrial gas turbine engines. Potential uses of this rig include investigations into environmental attack of turbine materials and coatings exposed to syngas, erosion, and thermal-mechanical fatigue. The principle activities during Phase 1 of this project included providing several conceptual designs for the test section, evaluating various syngas-fueled rig combustor concepts, comparing the various test section concepts and then selecting a configuration for detail design. Conceptual definition and requirements of auxiliary systems and facilities were also prepared. Implementation planning also progressed, with schedules prepared and future project milestones defined. The results of these tasks continue to show rig feasibility, both technically and economically.

  9. Advanced batteries for electric vehicles-A status report

    SciTech Connect

    Walsh, W.J.

    1981-01-01

    The candidate battery systems for electric vehicles have been evaluated on a common basis. The batteries with the highest probability of successful development and commercialization appear to be lead-acid, nickel-iron, nickel-zinc, zinc-chlorine, lithium-metal sulfide, and sodium sulfur. The relative development risk was assessed and compared to the desirability of the corresponding batteries.

  10. DEVELOPMENT OF ADVANCED ESFF (ELECTRICAL STIMULATION OF FABRIC FILTRATION) TECHNOLOGY

    EPA Science Inventory

    The report summarizes work on electrical stimulation of fabric filtration (ESFF) with the major objectives of defining the role of some primary variables and understanding the mechanisms of electrostatic enhancement. It was concluded that the magnitude of particle charge has a st...

  11. Electrical research on solar cells and photovoltaic materials

    NASA Technical Reports Server (NTRS)

    Orehotsky, J.

    1984-01-01

    The flat-plate solar cell array program which increases the service lifetime of the photovoltaic modules used for terrestrial energy applications is discussed. The current-voltage response characteristics of the solar cells encapsulated in the modules degrade with service time and this degradation places a limitation on the useful lifetime of the modules. The most desirable flat-plate array system involves solar cells consisting of highly polarizable materials with similar electrochemical potentials where the cells are encapsulated in polymers in which ionic concentrations and mobilities are negligibly small. Another possible mechanism limiting the service lifetime of the photovoltaic modules is the gradual loss of the electrical insulation characteristics of the polymer pottant due to water absorption or due to polymer degradation from light or heat effects. The mechanical properties of various polymer pottant materials and of electrochemical corrosion mechanisms in solar cell material are as follows: (1) electrical and ionic resistivity; (2) water absorption kinetics and water solubility limits; and (3) corrosion characterization of various metallization systems used in solar cell construction.

  12. Advanced Electric Distribution, Switching, and Conversion Technology for Power Control

    NASA Technical Reports Server (NTRS)

    Soltis, James V.

    1998-01-01

    The Electrical Power Control Unit currently under development by Sundstrand Aerospace for use on the Fluids Combustion Facility of the International Space Station is the precursor of modular power distribution and conversion concepts for future spacecraft and aircraft applications. This unit combines modular current-limiting flexible remote power controllers and paralleled power converters into one package. Each unit includes three 1-kW, current-limiting power converter modules designed for a variable-ratio load sharing capability. The flexible remote power controllers can be used in parallel to match load requirements and can be programmed for an initial ON or OFF state on powerup. The unit contains an integral cold plate. The modularity and hybridization of the Electrical Power Control Unit sets the course for future spacecraft electrical power systems, both large and small. In such systems, the basic hybridized converter and flexible remote power controller building blocks could be configured to match power distribution and conversion capabilities to load requirements. In addition, the flexible remote power controllers could be configured in assemblies to feed multiple individual loads and could be used in parallel to meet the specific current requirements of each of those loads. Ultimately, the Electrical Power Control Unit design concept could evolve to a common switch module hybrid, or family of hybrids, for both converter and switchgear applications. By assembling hybrids of a common current rating and voltage class in parallel, researchers could readily adapt these units for multiple applications. The Electrical Power Control Unit concept has the potential to be scaled to larger and smaller ratings for both small and large spacecraft and for aircraft where high-power density, remote power controllers or power converters are required and a common replacement part is desired for multiples of a base current rating.

  13. Cladding and Structural Materials for Advanced Nuclear Energy Systems

    SciTech Connect

    Was, G S; Allen, T R; Ila, D; C,; Levi,; Morgan, D; Motta, A; Wang, L; Wirth, B

    2011-06-30

    The goal of this consortium is to address key materials issues in the most promising advanced reactor concepts that have yet to be resolved or that are beyond the existing experience base of dose or burnup. The research program consists of three major thrusts: 1) high-dose radiation stability of advanced fast reactor fuel cladding alloys, 2) irradiation creep at high temperature, and 3) innovative cladding concepts embodying functionally-graded barrier materials. This NERI-Consortium final report represents the collective efforts of a large number of individuals over a period of three and a half years and included 9 PIs, 4 scientists, 3 post-docs and 12 students from the seven participating institutions and 8 partners from 5 national laboratories and 3 industrial institutions (see table). University participants met semi-annually and participants and partners met annually for meetings lasting 2-3 days and designed to disseminate and discuss results, update partners, address outstanding issues and maintain focus and direction toward achieving the objectives of the program. The participants felt that this was a highly successful program to address broader issues that can only be done by the assembly of a range of talent and capabilities at a more substantial funding level than the traditional NERI or NEUP grant. As evidence of the success, this group, collectively, has published 20 articles in archival journals and made 57 presentations at international conferences on the results of this consortium.

  14. NASA's Advanced Space Transportation Program: A Materials Overview

    NASA Technical Reports Server (NTRS)

    Clinton, R. G., Jr.

    1999-01-01

    The realization of low-cost assess to space is one of NASA's three principal goals or "pillars" under the Office of Aero-Space Technology. In accordance with the goals of this pillar, NASA's primary space transportation technology role is to develop and demonstrate next-generation technologies to enable the commercial launch industry to develop full-scale, low cost, highly reliable space launchers. The approach involves both ground-based technology demonstrations and flight demonstrators, including the X-33, X-34, Bantam, Reusable Launch Vehicle (RLV), and future experimental vehicles. Next generation space transportation vehicles and propulsion systems will require the development and implementation of advanced materials and processes. This presentation will provide an overview of advanced materials efforts which are focused on the needs of next generation space transportation systems. Applications described will include ceramic matrix composite (CMC) integrally bladed turbine disk (blisk); actively cooled CMC nozzle ramp for the aerospike engine; ablative thrust chamber/nozzle; and metal matrix composite turbomachinery housings.

  15. On fracture phenomena in advanced fiber composite materials.

    NASA Technical Reports Server (NTRS)

    Konish, H. J., Jr.; Swedlow, J. L.; Cruse, T. A.

    1972-01-01

    The extension of linear elastic fracture mechanics (LEFM) from metallic alloys to advanced fiber composite laminates is considered. LEFM is shown to be valid for both isotropic and anisotropic homogeneous continua; the applicability of LEFM to advanced fiber composites is thus dependent on the validity of a homogeneous model of such materials. An experimental program to determine the validity of such a model for graphite/epoxy laminates is reviewed. Such laminates are found to have an apparent fracture toughness, from which it is inferred that a homogeneous material model is valid for the particular specimen geometry and composite laminates considered. Strain energy release rates are calculated from the experimentally determined fracture toughness of the various laminates. These strain energy release rates are found to lie in one of two groups, depending upon whether crack extension required fiber failure or matrix failure. The latter case is further investigated. It is concluded that matrix failure is governed by the tensile stress normal to the crack path.

  16. Increasing Importance of Material Electrical Interaction with the Space Environment

    NASA Technical Reports Server (NTRS)

    Carruth, M. R., Jr.; Vaughn, Jason

    2000-01-01

    The electrical properties of materials have always been important for spacecraft in charging environments. However, in recent years consideration of interactions of materials and systems with the plasma environment has become more and more important in spacecraft design. This has primarily been driven by independent factors including increase in power and high voltage power systems, operation of tethered satellites, and science requirements for electrostatic clean spacecraft. Increased need for power has led to increased operating voltages for spacecraft. The Upper Atmospheric Research Satellite (UARS) was one of the first to operate at near 100 V solar array potential and demonstrate that the spacecraft floated nearly the entire voltage negative of the ionospheric plasma. The high voltage, 160 V, of the solar arrays on the International Space Station (ISS) led to the requirement to have a plasma contactor to control structure potential relative to the local plasma. Issues such as sputtering, dielectric breakdown, capacitive energy storage in the structure, space debris impact induced arcs and other arcing mechanisms had to be addressed. Recently commercial satellites, driven to higher voltages for efficiency, have experienced arcing problems which led to severe, permanent power degradation. The first tethered satellite, Tethered Satellite System (TSS), was deployed from the Space Shuttle. A conductive coating was developed which provided a low resistivity and also the required solar absorptivity and emittance. Other tether systems are being designed which will have similar requirements but also long life and "bare tether" designs are also being built for flight experiments. The wire requires an electrically conductive coating with proper thermal control properties, which a bare wire doesn't possess. Increasing sophistication of scientific instruments and measurements which scientists want to make have led to increasing requirements for conducting thermal control

  17. Advanced Industrial Materials (AIM) Program annual progress report, FY 1997

    SciTech Connect

    1998-05-01

    The Advanced Industrial Materials (AIM) Program is a part of the Office of Industrial Technologies (OIT), Energy Efficiency and Renewable Energy, US Department of Energy (DOE). The mission of AIM is to support development and commercialization of new or improved materials to improve energy efficiency, productivity, product quality, and reduced waste in the major process industries. OIT has embarked on a fundamentally new way of working with industries--the Industries of the Future (IOF) strategy--concentrating on the major process industries that consume about 90% of the energy and generate about 90% of the waste in the industrial sector. These are the aluminum, chemical, forest products, glass, metalcasting, and steel industries. OIT has encouraged and assisted these industries in developing visions of what they will be like 20 or 30 years into the future, defining the drivers, technology needs, and barriers to realization of their visions. These visions provide a framework for development of technology roadmaps and implementation plans, some of which have been completed. The AIM Program supports IOF by conducting research and development on materials to solve problems identified in the roadmaps. This is done by National Laboratory/industry/university teams with the facilities and expertise needed to develop new and improved materials. Each project in the AIM Program has active industrial participation and support.

  18. Combustion Synthesis of Advanced Porous Materials in Microgravity Environment

    NASA Technical Reports Server (NTRS)

    Zhang, X.; Moore, J. J.; Schowengerdt, F. D.; Johnson, D. P.

    1999-01-01

    Combustion synthesis, otherwise known as self-propagating high temperature synthesis (SHS), can be used to produce engineered advanced porous material implants which offer the possibility for bone ingrowth as well as a permanent structure framework for the long-term replacement of bone defects. The primary advantage of SHS is based on its rapid kinetics and favorable energetics. The structure and properties of materials produced by SHS are strongly dependent on the combustion reaction conditions. Combustion reaction conditions such as reaction stoichiometry, particle size, green density, the presence and use of diluents or inert reactants, and pre-heating of the reactants, will affect the exothermicity of the reaction. A number of conditions must be satisfied in order to obtain high porosity materials: an optimal amount of liquid, gas and solid phases must be present in the combustion front. Therefore, a balance among these phases at the combustion front must be created by the SHS reaction to successfully engineer a bone replacement material system. Microgravity testing has extended the ability to form porous products. The convective heat transfer mechanisms which operate in normal gravity, 1 g, constrain the combustion synthesis reactions. Gravity also acts to limit the porosity which may be formed as the force of gravity serves to restrict the gas expansion and the liquid movement during reaction. Infiltration of the porous product with other phases can modify both the extent of porosity and the mechanical properties.

  19. Brayton Power Conversion System Study to Advance Technology Readiness for Nuclear Electric Propulsion - Phase I

    SciTech Connect

    Frye, Patrick E.; Allen, Robert; Delventhal, Rex

    2005-02-06

    To investigate and mature space based nuclear power conversion technologies NASA awarded several contracts under Prometheus, the Nuclear Systems Program. The studies described in this paper were performed under one of those contracts, which was to investigate the use of a nuclear power conversion system based on the closed Brayton cycle (CBC). The conceptual design effort performed included BPCS (Brayton power conversion system) trade studies to minimize system weight and radiator area and advance the state of the art of BPCS technology. The primary requirements for studies were a power level of 100 kWe (to the PPU), a low overall power system mass (with a target of less than 3000 kg), and a lifetime of 15 years (10 years full power). For the radiation environment, the system was to operate in the generic space environment and withstand the extreme environments within the Jovian system. The studies defined a BPCS design traceable to NBP (Nuclear Electric Propulsion) requirements and suitable for future potential missions with a sound technology plan for TRL (Technical Readiness Level) advancement identified. The studies assumed a turbine inlet temperature {approx} 100C above the current the state of the art capabilities with materials issues identified and an approach for resolution developed. Analyses and evaluations of six HRS (heat rejection subsystem) concepts and PMAD (Power Management and Distribution) architecture trades will be discussed in the paper.

  20. Brayton Power Conversion System Study to Advance Technology Readiness for Nuclear Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Allen, Bog; Delventhal, Rex; Frye, Patrick

    2004-01-01

    Recently, there has been significant interest within the aerospace community to develop space based nuclear power conversion technologies especially for exploring the outer planets of our solar system where the solar energy density is very low. To investigate these technologies NASA awarded several contracts under Project Prometheus, the Nuclear Systems Program. The studies described in this paper were performed under one of those contracts, which was to investigate the use of a nuclear power conversion system based on the closed Brayton cycle (CBC).The investigation performed included BPCS (Brayton Power Conversion System) trade studies to minimize system weight and radiator area and advance the state of the art of BPCS technology. The primary requirements for studies were a power level of 100 kWe (to the PPU), a low overall power system mass and a lifetime of 15 years (10 years full power). For the radiation environment, the system was to be capable of operation in the generic space environment and withstand the extreme environments surrounding Jupiter. The studies defined a BPCS design traceable to NEP (Nuclear Electric Propulsion) requirements and suitable for future missions with a sound technology plan for technology readiness level (TRL) advancement identified. The studies assumed a turbine inlet temperature approx. 100 C above the current the state of the art capabilities with materials issues and related development tasks identified. Analyses and evaluations of six different HRS (heat rejection system) designs and three primary power management and distribution (PMAD) configurations will be discussed in the paper.

  1. Brayton Power Conversion System Study to Advance Technology Readiness for Nuclear Electric Propulsion — Phase I

    NASA Astrophysics Data System (ADS)

    Frye, Patrick E.; Allen, Robert; Delventhal, Rex

    2005-02-01

    To investigate and mature space based nuclear power conversion technologies NASA awarded several contracts under Prometheus, the Nuclear Systems Program. The studies described in this paper were performed under one of those contracts, which was to investigate the use of a nuclear power conversion system based on the closed Brayton cycle (CBC). The conceptual design effort performed included BPCS (Brayton power conversion system) trade studies to minimize system weight and radiator area and advance the state of the art of BPCS technology. The primary requirements for studies were a power level of 100 kWe (to the PPU), a low overall power system mass (with a target of less than 3000 kg), and a lifetime of 15 years (10 years full power). For the radiation environment, the system was to operate in the generic space environment and withstand the extreme environments within the Jovian system. The studies defined a BPCS design traceable to NBP (Nuclear Electric Propulsion) requirements and suitable for future potential missions with a sound technology plan for TRL (Technical Readiness Level) advancement identified. The studies assumed a turbine inlet temperature ˜ 100C above the current the state of the art capabilities with materials issues identified and an approach for resolution developed. Analyses and evaluations of six HRS (heat rejection subsystem) concepts and PMAD (Power Management and Distribution) architecture trades will be discussed in the paper.

  2. Validation of an Advanced Material Model for Simulating the Impact and Shock Response of Composite Materials

    NASA Astrophysics Data System (ADS)

    Clegg, Richard A.; Hayhurst, Colin J.; Nahme, Hartwig

    2002-07-01

    Composite materials are now commonly used as ballistic and hypervelocity protection materials and the demand for simulation of impact on these materials is increasing. A new material model specifically designed for the shock response of anisotropic materials has been developed and implemented in the hydrocode AUTODYN. The model allows for the representation of non-linear shock effects in combination with anisotropic material stiffness and damage. The coupling of the equation of state and anisotropic response is based on the methodology proposed by Anderson et al. [2]. An overview of the coupled formulation is described in order to point out the important assumptions, key innovations and basic theoretical framework. The coupled model was originally developed by Century Dynamics and Fhg-EMI for assessing the hypervelocity impact response of composite satellite protection systems [1]. It was also identified that the developed model should also offer new possibilities and capabilities for modelling modern advanced armour materials. Validation of the advanced composite model is firstly shown via simulations of uniaxial strain flyer plate experiments on aramid and polyethylene fibre composite systems. Finally, practical application of the model as implemented in AUTODYN is demonstrated through the simulation of ballistic and hypervelocity impact events. Comparison with experiment is given where possible.

  3. An assessment of research and development leadership in advanced batteries for electric vehicles

    SciTech Connect

    Bruch, V.L.

    1994-02-01

    Due to the recently enacted California regulations requiring zero emission vehicles be sold in the market place by 1998, electric vehicle research and development (R&D) is accelerating. Much of the R&D work is focusing on the Achilles` heel of electric vehicles -- advanced batteries. This report provides an assessment of the R&D work currently underway in advanced batteries and electric vehicles in the following countries: Denmark, France, Germany, Italy, Japan, Russia, and the United Kingdom. Although the US can be considered one of the leading countries in terms of advanced battery and electric vehicle R&D work, it lags other countries, particularly France, in producing and promoting electric vehicles. The US is focusing strictly on regulations to promote electric vehicle usage while other countries are using a wide variety of policy instruments (regulations, educational outreach programs, tax breaks and subsidies) to encourage the use of electric vehicles. The US should consider implementing additional policy instruments to ensure a domestic market exists for electric vehicles. The domestic is the largest and most important market for the US auto industry.

  4. An assessment of research and development leadership in advanced batteries for electric vehicles

    NASA Astrophysics Data System (ADS)

    Bruch, V. L.

    1994-02-01

    Due to the recently enacted California regulations requiring zero emission vehicles be sold in the market place by 1998, electric vehicle research and development (R&D) is accelerating. Much of the R&D work is focusing on the Achilles' heel of electric vehicles -- advanced batteries. This report provides an assessment of the R&D work currently underway in advanced batteries and electric vehicles in the following countries: Denmark, France, Germany, Italy, Japan, Russia, and the United Kingdom. Although the US can be considered one of the leading countries in terms of advanced battery and electric vehicle R&D work, it lags other countries, particularly France, in producing and promoting electric vehicles. The US is focusing strictly on regulations to promote electric vehicle usage while other countries are using a wide variety of policy instruments (regulations, educational outreach programs, tax breaks and subsidies) to encourage the use of electric vehicles. The US should consider implementing additional policy instruments to ensure a domestic market exists for electric vehicles. The domestic is the largest and most important market for the US auto industry.

  5. Comparison of advanced battery technologies for electric vehicles

    SciTech Connect

    Dickinson, B.E.; Lalk, T.R.; Swan, D.H.

    1993-12-31

    Battery technologies of different chemistries, manufacture and geometry were evaluated as candidates for use in Electric Vehicles (EV). The candidate batteries that were evaluated include four single cell and seven multi-cell modules representing four technologies: Lead-Acid, Nickel-Cadmium, Nickel-Metal Hydride and Zinc-Bromide. A standard set of testing procedures for electric vehicle batteries, based on industry accepted testing procedures, and any tests which were specific to individual battery types were used in the evaluations. The batteries were evaluated by conducting performance tests, and by subjecting them to cyclical loading, using a computer controlled charge--discharge cycler, to simulate typical EV driving cycles. Criteria for comparison of batteries were: performance, projected vehicle range, cost, and applicability to various types of EVs. The four battery technologies have individual strengths and weaknesses and each is suited to fill a particular application. None of the batteries tested can fill every EV application.

  6. Laboratory evaluation of advanced battery technologies for electric vehicle applications

    SciTech Connect

    DeLuca, W.H.; Kulaga, J.E.; Hogrefe, R.L.; Tummilo, A.F.; Webster, C.E.

    1989-01-01

    During 1988, battery technology evaluations were performed for the Department of Energy and Electric Power Research Institute at the Argonne Analysis and Diagnostic Laboratory. Cells and multicell modules from four developers were examined to determine their performance and life characteristics for electric vehicle propulsion applications. The results provide an interim measure of the progress being made in battery RandD programs, a comparison of battery technologies, and a source of basic data for modeling and continuing RandD. This paper summarizes the performance and life characterizations of twelve single cells and six 3- to 24-cell modules that encompass four technologies (Na/S, Ni/Fe, lead-acid, and Fe/Air). 4 figs., 1 tab.

  7. Laboratory evaluation of advanced battery technologies for electric vehicle applications

    SciTech Connect

    DeLuca, W.H.; Kulaga, J.E.; Hogrefe, R.L.; Tummillo, A.F.; Webster, C.E.

    1989-01-01

    During 1988, battery technology evaluations were performed for the Department of Energy and Electric Power Research Institute at the Argonne Analysis and Diagnostic Laboratory. Cells and multicell modules from four developers were examined to determine their performance and life characteristics for electric vehicle propulsion applications. the results provide an interim measure of the progress being made in battery R and D programs, a comparison of battery technologies, and a source of basic data for modeling and continuing R and D. This paper summarizes the performance and life characterizations of twelve single cells and six 3- to 24-cell modules that encompass four technologies (Na/S, Ni/Fe, lead-acid, and Fe/Air).

  8. Advances in Optimizing Weather Driven Electric Power Systems.

    NASA Astrophysics Data System (ADS)

    Clack, C.; MacDonald, A. E.; Alexander, A.; Dunbar, A. D.; Xie, Y.; Wilczak, J. M.

    2014-12-01

    The importance of weather-driven renewable energies for the United States (and global) energy portfolio is growing. The main perceived problems with weather-driven renewable energies are their intermittent nature, low power density, and high costs. The National Energy with Weather System Simulator (NEWS) is a mathematical optimization tool that allows the construction of weather-driven energy sources that will work in harmony with the needs of the system. For example, it will match the electric load, reduce variability, decrease costs, and abate carbon emissions. One important test run included existing US carbon-free power sources, natural gas power when needed, and a High Voltage Direct Current power transmission network. This study shows that the costs and carbon emissions from an optimally designed national system decrease with geographic size. It shows that with achievable estimates of wind and solar generation costs, that the US could decrease its carbon emissions by up to 80% by the early 2030s, without an increase in electric costs. The key requirement would be a 48 state network of HVDC transmission, creating a national market for electricity not possible in the current AC grid. These results were found without the need for storage. Further, we tested the effect of changing natural gas fuel prices on the optimal configuration of the national electric power system. Another test that was carried out was an extension to global regions. The extension study shows that the same properties found in the US study extend to the most populous regions of the planet. The extra test is a simplified version of the US study, and is where much more research can be carried out. We compare our results to other model results.

  9. Recent Advances in Electrical Resistance Preheating of Aluminum Reduction Cells

    NASA Astrophysics Data System (ADS)

    Ali, Mohamed Mahmoud; Kvande, Halvor

    2016-06-01

    ABSTRACT There are two mainpreheating methods that are used nowadays for aluminum reduction cells. One is based on electrical resistance preheating with a thin bed of small coke and/or graphite particles between the anodes and the cathode carbon blocks. The other is flame preheating, where two or more gas or oil burners are used. Electrical resistance preheating is the oldest method, but is still frequently used by different aluminum producers. Many improvements have been made to this method by different companies over the last decade. In this paper, important points pertaining to the preparation and preheating of these cells, as well as measurements made during the preheating process and evaluation of the performance of the preheating, are illustrated. The preheating times of these cells were found to be between 36 h and 96 h for cell currents between 176 kA and 406 kA, while the resistance bed thickness was between 13 mm and 60 mm. The average cathode surface temperature at the end of the preheating was usually between 800°C and 950°C. The effect of the preheating methods on cell life is unclear and no quantifiable conclusions can be drawn. Some works carried out in the mathematical modeling area are also discussed. It is concluded that there is a need for more studies with real situations for preheated cells on the basis of actual measurements. The expected development in electrical resistance preheating of aluminum reduction cells is also summarized.

  10. PREFACE Conference on Advanced Materials and Nanotechnology (CAMAN 2009)

    NASA Astrophysics Data System (ADS)

    Ali, Aidy

    2011-02-01

    This special issue of IOP Conference Series: Materials science and Engineering contains papers contributed to the Conference on Advanced Materials and Nanotechnology (CAMAN 2009) held on 3-5 November 2009 in Putra World Trade Centre (PWTC), Kuala Lumpur, Malaysia. The objective of the congress is to provide a platform for professionals, academicians and researchers to exchange views, findings, ideas and experiences on advanced science and technology. After careful refereeing of all manuscripts, 50 papers were selected for publications in this issue. The policy of editing was the content of the material and its rapid dissemination was more important than its form. In 2009, the conference received close to 120 papers from leading researchers and participants from countries such as Iran, India, Switzerland, Myanmar, Nigeria, Canada, Yemen and Malaysia. We strongly hope the new ideas and results presented will stimulate and enhance the progress of research on the above conference theme. We are grateful to all the authors for their papers and presentations in this conference. They are also the ones who help make this conference possible through their hard work in the preparation of the manuscripts. We would also like to offer our sincere thanks to all the invited speakers who came to share their knowledge with us. We would also like to acknowledge the untiring efforts of the reviewers, research assistants and students in meeting deadlines and for their patience and perseverance. We wish to thank all the authors who contributed papers to the conference and all reviewers for their efforts to review the papers as well as the sponsors. We would also like to thank the members of the CAMAN 2009 Organising Committee and the International Advisory Committee for their efforts in making the conference a success. Thank you very much indeed. Guest Editor Aidy Ali

  11. Quality Assurance Protocol for AFCI Advanced Structural Materials Testing

    SciTech Connect

    Busby, Jeremy T

    2009-05-01

    The objective of this letter is to inform you of recent progress on the development of advanced structural materials in support of advanced fast reactors and AFCI. As you know, the alloy development effort has been initiated in recent months with the procurement of adequate quantities of the NF616 and HT-UPS alloys. As the test alloys become available in the coming days, mechanical testing, evaluation of optimizing treatments, and screening of environmental effects will be possible at a larger scale. It is therefore important to establish proper quality assurance protocols for this testing effort in a timely manner to ensure high technical quality throughout testing. A properly implemented quality assurance effort will also enable preliminary data taken in this effort to be qualified as NQA-1 during any subsequent licensing discussions for an advanced design or actual prototype. The objective of this report is to describe the quality assurance protocols that will be used for this effort. An essential first step in evaluating quality protocols is assessing the end use of the data. Currently, the advanced structural materials effort is part of a long-range, basic research and development effort and not, as yet, involved in licensing discussions for a specific reactor design. After consultation with Mark Vance (an ORNL QA expert) and based on the recently-issued AFCI QA requirements, the application of NQA-1 quality requirements will follow the guidance provided in Part IV, Subpart 4.2 of the NQA-1 standard (Guidance on Graded Application of QA for Nuclear-Related Research and Development). This guidance mandates the application of sound scientific methodology and a robust peer review process in all phases, allowing for the data to be qualified for use even if the programmatic mission changes to include licensing discussions of a specific design or prototype. ORNL has previously implemented a QA program dedicated to GNEP activities and based on an appropriately graded

  12. Advanced Stirling Duplex Materials Assessment for Potential Venus Mission Heater Head Application

    NASA Technical Reports Server (NTRS)

    Ritzert, Frank; Nathal, Michael V.; Salem, Jonathan; Jacobson, Nathan; Nesbitt, James

    2011-01-01

    This report will address materials selection for components in a proposed Venus lander system. The lander would use active refrigeration to allow Space Science instrumentation to survive the extreme environment that exists on the surface of Venus. The refrigeration system would be powered by a Stirling engine-based system and is termed the Advanced Stirling Duplex (ASD) concept. Stirling engine power conversion in its simplest definition converts heat from radioactive decay into electricity. Detailed design decisions will require iterations between component geometries, materials selection, system output, and tolerable risk. This study reviews potential component requirements against known materials performance. A lower risk, evolutionary advance in heater head materials could be offered by nickel-base superalloy single crystals, with expected capability of approximately 1100C. However, the high temperature requirements of the Venus mission may force the selection of ceramics or refractory metals, which are more developmental in nature and may not have a well-developed database or a mature supporting technology base such as fabrication and joining methods.

  13. Advanced proton-exchange materials for energy efficient fuel cells.

    SciTech Connect

    Fujimoto, Cy H.; Grest, Gary Stephen; Hickner, Michael A.; Cornelius, Christopher James; Staiger, Chad Lynn; Hibbs, Michael R.

    2005-12-01

    The ''Advanced Proton-Exchange Materials for Energy Efficient Fuel Cells'' Laboratory Directed Research and Development (LDRD) project began in October 2002 and ended in September 2005. This LDRD was funded by the Energy Efficiency and Renewable Energy strategic business unit. The purpose of this LDRD was to initiate the fundamental research necessary for the development of a novel proton-exchange membranes (PEM) to overcome the material and performance limitations of the ''state of the art'' Nafion that is used in both hydrogen and methanol fuel cells. An atomistic modeling effort was added to this LDRD in order to establish a frame work between predicted morphology and observed PEM morphology in order to relate it to fuel cell performance. Significant progress was made in the area of PEM material design, development, and demonstration during this LDRD. A fundamental understanding involving the role of the structure of the PEM material as a function of sulfonic acid content, polymer topology, chemical composition, molecular weight, and electrode electrolyte ink development was demonstrated during this LDRD. PEM materials based upon random and block polyimides, polybenzimidazoles, and polyphenylenes were created and evaluated for improvements in proton conductivity, reduced swelling, reduced O{sub 2} and H{sub 2} permeability, and increased thermal stability. Results from this work reveal that the family of polyphenylenes potentially solves several technical challenges associated with obtaining a high temperature PEM membrane. Fuel cell relevant properties such as high proton conductivity (>120 mS/cm), good thermal stability, and mechanical robustness were demonstrated during this LDRD. This report summarizes the technical accomplishments and results of this LDRD.

  14. Damping capacity measurements for characterization of degradation in advanced materials

    SciTech Connect

    Mantena, R.; Gibson, R.F.; Place, T.A.

    1986-01-01

    This paper describes the application of damping capacity measurements for characterization of degradation in advanced materials. A recently developed impulse-frequency response technique was used to obtain damping capacity measurements on crossplied E-glass/epoxy laminates which had been subjected to four-point bending and cantilever bending to produce matrix cracking in the transverse plies. The size and location of the damage zone were correlated with changes in damping. With the expected introduction of Rapidly Solidified Alloys (RSA) as effective alternatives to conventional materials, the applicability of damping capacity measurements as a nondestructive means of evaluating degradation in these materials was also studied. A conventional A710 structural steel having three different microstructures was used for developing the methodology to be used later on RSA specimens. It is shown that damping is more sensitive to matrix cracking than stiffness is in E-glass/epoxy composite specimens. In the case of A710 steel, the damping changes at low strain, though significant, do not correlate with the mechanical property data. Damping data at high strains does correlate with the mechanical property data, however.

  15. Numerical Forming Simulations and Optimisation in Advanced Materials

    NASA Astrophysics Data System (ADS)

    Huétink, J.; van den Boogaard, A. H.; Geijselears, H. J. M.; Meinders, T.

    2007-05-01

    With the introduction of new materials as high strength steels, metastable steels and fibre reinforced composites, the need for advanced physically valid constitutive models arises. In finite deformation problems constitutive relations are commonly formulated in terms the Cauchy stress as a function of the elastic Finger tensor and an objective rate of the Cauchy stress as a function of the rate of deformation tensor. For isotropic materials models this is rather straightforward, but for anisotropic material models, including elastic anisotropy as well as plastic anisotropy, this may lead to confusing formulations. It will be shown that it is more convenient to define the constitutive relations in terms of invariant tensors referred to the deformed metric. Experimental results are presented that show new combinations of strain rate and strain path sensitivity. An adaptive through- thickness integration scheme for plate elements is developed, which improves the accuracy of spring back prediction at minimal costs. A procedure is described to automatically compensate the CAD tool shape numerically to obtain the desired product shape. Forming processes need to be optimized for cost saving and product improvement. Until recently, a trial-and-error process in the factory primarily did this optimization. An optimisation strategy is proposed that assists an engineer to model an optimization problem that suits his needs, including an efficient algorithm for solving the problem.

  16. Temperature controlled material irradiation in the advanced test reactor

    NASA Astrophysics Data System (ADS)

    Ingram, F. W.; Palmer, A. J.; Stites, D. J.

    1998-10-01

    The United States Department of Energy (US DOE) has initiated the development of an Irradiation Test Vehicle (ITV) for fusion materials irradiation at the Advanced Test Reactor (ATR) in Idaho Falls, Idaho, USA. The ITV is capable of providing neutron spectral tailoring and individual temperature control for up to 15 experiment capsules simultaneously. The test vehicle consists of three In-Pile Tubes (IPTs) running the length of the reactor vessel. These IPTs are kept dry and test trains with integral instrumentation are inserted and removed through a transfer shield plate above the reactor vessel head. The test vehicle is designed to irradiate specimens as large as 2.2 cm in diameter, at temperatures of 250-800°C, achieving neutron damage rates as high as 10 displacements per atom per year. The high fast to thermal neutron flux ratio required for fusion materials testing is accomplished by using an aluminum filler to displace as much water as possible from the flux trap and surrounding the filler piece with a ring of replaceable neutron absorbing material. The gas blend temperature control system remains in place from test to test, thus hardware costs for new tests are limited to the experiment capsule train and integral instrumentation.

  17. Methods for integrating optical fibers with advanced aerospace materials

    NASA Astrophysics Data System (ADS)

    Poland, Stephen H.; May, Russell G.; Murphy, Kent A.; Claus, Richard O.; Tran, Tuan A.; Miller, Mark S.

    1993-07-01

    Optical fibers are attractive candidates for sensing applications in near-term smart materials and structures, due to their inherent immunity to electromagnetic interference and ground loops, their capability for distributed and multiplexed operation, and their high sensitivity and dynamic range. These same attributes also render optical fibers attractive for avionics busses for fly-by-light systems in advanced aircraft. The integration of such optical fibers with metal and composite aircraft and aerospace materials, however, remains a limiting factor in their successful use in such applications. This paper first details methods for the practical integration of optical fiber waveguides and cable assemblies onto and into materials and structures. Physical properties of the optical fiber and coatings which affect the survivability of the fiber are then considered. Mechanisms for the transfer of the strain from matrix to fiber for sensor and data bus fibers integrated with composite structural elements are evaluated for their influence on fiber survivability, in applications where strain or impact is imparted to the assembly.

  18. Electrical test structures replicated in silicon-on-insulator material

    SciTech Connect

    Cresswell, M.W.; Ghoshtagore, R.N.; Allen, R.A.; Linholm, L.W.; Villarrubia, J.S.; Sniegowski, J.J.

    1996-02-27

    Measurements of the linewidths of submicrometer features made by different metrology techniques have frequently been characterized by differences of up to 90 nm. The purpose of the work reported here is to address the special difficulties that this phenomenon presents to the certification of reference materials for the calibration of linewidth-measurement instruments. Accordingly, a new test structure has been designed, fabricated, and undergone preliminary tests. Its distinguishing characteristics are assured cross-sectional profile geometries with known side-wall slopes, surface planarity, and compositional uniformity when it is formed in mono-crystalline material at selected orientations to the crystal lattice. To allow the extraction of electrical linewidth, the structure is replicated in a silicon film of uniform conductivity which is separated from the silicon substrate by a buried oxide layer. The utilization of a Silicon-On-Insulator (SKI) substrate further allows the selective removal of substrate material from local regions below the reference features, thus facilitating measurements by optical and electron-beam transmission microscopy. The combination of planar feature surfaces having known side-wall slopes is anticipated to eliminate factors which are believed to be responsible for methods divergence in linewidth measurements, a capability which is a prerequisite for reliable certification of the linewidths of features on reference materials.

  19. Development of Tailorable Electrically Conductive Thermal Control Material Systems

    NASA Technical Reports Server (NTRS)

    Deshpande, M. S.; Harada, Y.

    1997-01-01

    The optical characteristics of surfaces on spacecraft are fundamental parameters in controlling its temperature. Passive thermal control coatings with designed solar absorptance and infrared emittance properties have been developed and have been in use for some time. In this total space environment, the coating must be stable and maintain its desired optical properties as well as mechanical properties for the course of the mission lifetime. The mission lifetimes are increasing and in our quest to save weight, newer substrates are being integrated which limit electrical grounding schemes. All of this has added to already existing concerns about spacecraft charging and related spacecraft failures or operational failures. The concern is even greater for thermal control surfaces that are very large. One way of alleviating such concerns is to design new thermal control material systems (TCMS) that can help to mitigate charging via providing charge leakage paths. The objective of this program was to develop two types of passive electrically conductive TCMS. The first was a highly absorbing/emitting black surface and the second was a low (alpha(sub s)/epsilon(sub N)) type white surface. The surface resistance goals for the black absorber was 10(exp 4) to 10(exp 9) Omega/square, and for the white surfaces it was 10(exp 6) to 10(exp 10) Omega/square. Several material system concepts were suggested and evaluated for space environment stability and electrical performance characterization. Our efforts in designing and evaluating these material systems have resulted in several developments. New concepts, pigments and binders have been developed to provide new engineering quality TCMS. Some of these have already found application on space hardware, some are waiting to be recognized by thermal designers, and some require further detailed studies to become state-of-the-art for future space hardware and space structures. Our studies on baseline state-of-the-art materials and

  20. Polymer/inorganic nanocomposites with tailored hierarchical structure as advanced dielectric materials

    SciTech Connect

    Manias, Evangelos; Randall, Clive; Tomer, Vivek; Polyzos, Georgios

    2012-01-01

    Most advances and commercial successes of polymer/inorganic nanocomposites rely only on the dispersion of nanoparticles in a polymer matrix. Such approaches leave untapped opportunities where performance can be improved by controlling the larger length-scale structures. Here, we review selected examples where the hierarchical structure (from millimeter to nanometer) is tailored to control the transport properties of the materials, giving rise to marked property enhancements, relevant to dielectric materials for power capacitors. These examples address composite structures that are self-assembled, both at the nm and the micron scales, and, thus, can be produced using standard industrial practices. Specifically, polyethylene (PE) blends or poly(vinylidene fluoride) (PVDF) copolymers are reinforced with nanofillers; these composites are designed with high filler orientation, which yielded marked improvements in electric-field breakdown strength and, consequently, large improvements in their recoverable energy densities.

  1. Advanced Hall Electric Propulsion for Future In-space Transportation

    NASA Technical Reports Server (NTRS)

    Oleson, Steven R.; Sankovic, John M.

    2001-01-01

    The Hall thruster is an electric propulsion device used for multiple in-space applications including orbit raising, on-orbit maneuvers, and de-orbit functions. These in-space propulsion functions are currently performed by toxic hydrazine monopropellant or hydrazine derivative/nitrogen tetroxide bi-propellant thrusters. The Hall thruster operates nominally in the 1500 sec specific impulse regime. It provides greater thrust to power than conventional gridded ion engines, thus reducing trip times and operational life when compared to that technology in Earth orbit applications. The technology in the far term, by adding a second acceleration stage, has shown promise of providing over 4000s Isp, the regime of the gridded ion engine and necessary for deep space applications. The Hall thruster system consists of three parts, the thruster, the power processor, and the propellant system. The technology is operational and commercially available at the 1.5 kW power level and 5 kW application is underway. NASA is looking toward 10 kW and eventually 50 kW-class engines for ambitious space transportation applications. The former allows launch vehicle step-down for GEO missions and demanding planetary missions such as Europa Lander, while the latter allows quick all-electric propulsion LEO to GEO transfers and non-nuclear transportation human Mars missions.

  2. PREFACE: International Conference on Advanced Materials (ICAM 2015)

    NASA Astrophysics Data System (ADS)

    El-Khateeb, Mohammad Y.

    2015-10-01

    It is with great pleasure to welcome you to the "International Conference of Advanced Materials ICAM 2015" that will take place at Jordan University of Science and Technology (JUST), Irbid, Jordan. This year, the conference coincides with the coming of spring in Jordan; we hope the participants will enjoy the colors and fragrance of April in Jordan. The call for papers attracted submissions of over a hundred abstracts from twenty one different countries. These papers are going to be classified under four plenary lectures, fifteen invited papers, thirty five oral presentations and more than sixty posters covering the different research areas of the conference. The ICAM conference focuses on new advances in research in the field of materials covering chemical, physical and biological aspects. ICAM includes representatives from academia, industry, governmental and private sectors. The plenary and invited speakers will present, discuss, promote and disseminate research in all fields of advanced materials. Topics range from synthesis, applications, and solid state to nano-materials. In addition, talented junior investigators will present their best ongoing research at a poster session. We have also organized several workshops contiguous to the main conference, such as the one-day workshop on "Particle Surface Modification for Improved Applications". The purpose of this short course was to introduce interested materials technologists to several methodologies that have been developed to modify the surfaces of particulate matter. Moreover, a pre-conference workshop on "Communication in Science" was conducted for young scientists. The main goal of this workshop was to train young scientists in matters of interdisciplinary scientific communications. In addition to the scientific program, the attendees will have a chance to discover the beauty of Jordan, a land of rich history and varied culture. Numerous social events that will provide opportunities to renew old contacts and

  3. Advanced Redox Flow Batteries for Stationary Electrical Energy Storage

    SciTech Connect

    Li, Liyu; Kim, Soowhan; Xia, Guanguang; Wang, Wei; Yang, Zhenguo

    2012-03-19

    This report describes the status of the advanced redox flow battery research being performed at Pacific Northwest National Laboratories for the U.S. Department of Energy’s Energy Storage Systems Program. The Quarter 1 of FY2012 Milestone was completed on time. The milestone entails completion of evaluation and optimization of single cell components for the two advanced redox flow battery electrolyte chemistries recently developed at the lab, the all vanadium (V) mixed acid and V-Fe mixed acid solutions. All the single cell components to be used in future kW-scale stacks have been identified and optimized in this quarter, which include solution electrolyte, membrane or separator; carbon felt electrode and bi-polar plate. Varied electrochemical, chemical and physical evaluations were carried out to assist the component screening and optimization. The mechanisms of the battery capacity fading behavior for the all vanadium redox flow and the Fe/V battery were discovered, which allowed us to optimize the related cell operation parameters and continuously operate the system for more than three months without any capacity decay.

  4. Advances in thin film photonics: materials, science, and technology

    NASA Astrophysics Data System (ADS)

    Fortmann, Charles M.; Tonucci, Ronald J.; Anderson, Wayne A.; Teplin, C. W.; Mahan, A. H.

    2003-10-01

    Control of refractive index in amorphous silicon materials is investigated. Elementary waveguide structures were prepared on two micron thick amorphous silicon by photon lithographic patterning of a silver masking layer. Hydrogen was implanted at fluence of ~5×1017 cm2 for three energies, 50, 100 and 175 KeV yielding a total does of ~1.5×1018 cm2 consistent with a 10% increase in atoms due to the hydrogen addition. The optical properties of the implanted and non-implanted regions were probed as a function of low temperature annealing. The optical band gap shift to higher energy was consistent with hydrogen addition. Some darkening, absorption increase, were noted on the implanted regions. However, low temperature annealing is known to remove dangling bond damage in amorphous silicon. Prospects of utilizing these waveguides to probe light induced optical changes in amorphous silicon is described as well as the prospects of more advanced devices.

  5. A Novel Approach to Material Development for Advanced Reactor Systems

    SciTech Connect

    Was, G.S.; Atzmon, M.; Wang, L.

    1999-12-22

    OAK B188 A Novel Approach to Material Development for Advanced Reactor Systems. Year one of this project had three major goals. First, to specify, order and install a new high current ion source for more rapid and stable proton irradiation. Second, to assess the use low temperature irradiation and chromium pre-enrichment in an effort to isolate a radiation damage microstructure in stainless steels without the effects of RIS. Third, to prepare for the irradiation of reactor pressure vessel steel and Zircaloy. In year 1 quarter 1, the project goal was to order the high current ion source and to procure and prepare samples of stainless steel for low temperature proton irradiation.

  6. A Novel Approach to Material Development for Advanced Reactor Systems

    SciTech Connect

    Was, G.S.; Atzmon, M.; Wang, L.

    2000-06-27

    OAK B188 A Novel Approach to Material Development for Advanced Reactor Systems. Year one of this project had three major goals. First, to specify, order and install a new high current ion source for more rapid and stable proton irradiation. Second, to assess the use of low temperature irradiation and chromium pre-enrichment in an effort to isolate a radiation damage microstructure in stainless steel without the effects of RIS. Third, to initiate irradiation of reactor pressure vessel steel and Zircaloy. In year 1 quarter 3, the project goal was to complete irradiation of model alloys of RPV steels for a range of doses and begin sample characterization. We also planned to prepare samples for microstructure isolation in stainless steels, and to identify sources of Zircaloy for irradiation and characterization.

  7. Advanced Lithium Ion Battery Materials Prepared with Atomic Layer Deposition

    NASA Astrophysics Data System (ADS)

    Cavanagh, Andrew S.

    As the world consumes the dwindling supply of fossil fuels, an alternative to gasoline powered vehicles will become necessary. Lithium ion batteries (LIBs) are emerging as the dominant power source for portable electronics, and are seen as a promising energy source in the development of electric vehicles. Current LIB technology is not well suited for vehicles, increases in the energy density, power density and durability are needed before LIB are ready for widespread use in electric vehicles. LiCoO2 and graphite are the dominant cathode and anode active materials, respectively in LIBs. On the cathode side, instabilities in LiCoO 2 can lead to the deterioration of the LIB. Decomposition of electrolyte on the graphite anode surface to form a solid-electrolyte interphase (SEI) consumes lithium from the cathode resulting in a lower battery capacity. Instabilities in the in the SEI can result in catastrophic battery failure. Previous studies have employed metal oxides films, typically grown with wet chemical techniques, to stabilize LiCoO2 and mitigate the formation of the SEI on graphite. The thicknesses of films grown with wet chemical techniques was typically ˜50--1000 A. In order to achieve higher power densities, the particle size of LIB active materials is being scaled down. As active materials get smaller the mass contribution of a protective film can become a significant fraction of the total mass. Atomic layer deposition (ALD) has been used to grow ultra thin films of Al2O3 on LiCoO2 and graphite. By altering the interaction between the active material and the battery electrolyte it was possible to improve the stability of both LiCoO2 and graphite electrodes in LIBs. In the case of graphite, the Al2O3 film may be thought of as an artificial SEI. During the initial charge-discharge cycle of a LIB, the electrolyte decomposes on the anode to form the SEI. The formation of the SEI is believed to prevent further decomposition of the electrolyte on the anode surface

  8. An outdoor exposure testing program for optical materials used in solar thermal electric technologies

    SciTech Connect

    Wendelin, T.; Jorgensen, G.

    1994-01-01

    Developing low-cost, durable advanced optical materials is important for making solar thermal energy. technologies viable for electricity production. The objectives of a new outdoor testing program recently initiated by the National Renewable Energy Laboratory (NREL) are to determine the expected lifetimes of candidate reflector materials and demonstrate their optical durability in real-world service conditions. NREL is working with both utilities and industry in a collaborative effort to achieve these objectives. To date, simulated/accelerated exposure testing of these materials has not been correlated with actual outdoor exposure testing. Such a correlation is desirable to provide confidence in lifetime predictions based upon accelerated weathering results. This outdoor testing program will allow outdoor exposure data to be obtained for realistic environments and will establish a data base for correlating simulated/accelerated outdoor exposure data with actual outdoor exposure data. In this program, candidate reflector materials are subjected to various outdoor exposure conditions in a network of sites across the southwestern United States. Important meteorological data are continuously recorded at these sites; these data will be analyzed for possible correlations with material optical performance. Weathered samples are characterized on a regular basis using a series of optical tests. These tests provide the basis for tracking material performance and durability with exposure time in the various outdoor environments. This paper describes the outdoor testing program in more detail including meteorological monitoring capabilities and the optical tests that are performed on these materials.

  9. Strongly coupled inorganic/nanocarbon hybrid materials for advanced electrocatalysis.

    PubMed

    Liang, Yongye; Li, Yanguang; Wang, Hailiang; Dai, Hongjie

    2013-02-13

    Electrochemical systems, such as fuel cell and water splitting devices, represent some of the most efficient and environmentally friendly technologies for energy conversion and storage. Electrocatalysts play key roles in the chemical processes but often limit the performance of the entire systems due to insufficient activity, lifetime, or high cost. It has been a long-standing challenge to develop efficient and durable electrocatalysts at low cost. In this Perspective, we present our recent efforts in developing strongly coupled inorganic/nanocarbon hybrid materials to improve the electrocatalytic activities and stability of inorganic metal oxides, hydroxides, sulfides, and metal-nitrogen complexes. The hybrid materials are synthesized by direct nucleation, growth, and anchoring of inorganic nanomaterials on the functional groups of oxidized nanocarbon substrates including graphene and carbon nanotubes. This approach affords strong chemical attachment and electrical coupling between the electrocatalytic nanoparticles and nanocarbon, leading to nonprecious metal-based electrocatalysts with improved activity and durability for the oxygen reduction reaction for fuel cells and chlor-alkali catalysis, oxygen evolution reaction, and hydrogen evolution reaction. X-ray absorption near-edge structure and scanning transmission electron microscopy are employed to characterize the hybrids materials and reveal the coupling effects between inorganic nanomaterials and nanocarbon substrates. Z-contrast imaging and electron energy loss spectroscopy at single atom level are performed to investigate the nature of catalytic sites on ultrathin graphene sheets. Nanocarbon-based hybrid materials may present new opportunities for the development of electrocatalysts meeting the requirements of activity, durability, and cost for large-scale electrochemical applications. PMID:23339685

  10. Advances in the application of in situ electrical resistance heating

    SciTech Connect

    Smith, Gregory J.; Beyke, Gregory

    2007-07-01

    Electrical Resistance Heating (ERH) is an aggressive in situ thermal remediation technology that was developed by the U.S. Department of Energy from the original oil production technology to enhance vapor extraction remediation technologies in low permeability soils. Soil and groundwater are heated by the passage of electrical current through saturated and unsaturated soil between electrodes, not by the electrodes themselves. It is the resistance to the flow of electrical current that results in increased subsurface temperatures, and this is typically applied to the boiling point of water. It is estimated that more than 75 ERH applications have been performed. Capacity to perform these projects has increased over the years, and as many as 15 to 20 of these applications now being performed at any given time, mainly in North America, with some European applications. While the main focus has been to vaporize volatile organic compounds, as one would expect other semi-volatile and non-volatile organic compounds have also been encountered, resulting in observations of chemical and physical reactions that have not been normally incorporated into environmental restoration projects. One such reaction is hydrolysis, which is slow under normal groundwater temperatures, becomes very rapid under temperatures that can easily be achieved using ERH. As a result, these chemical and physical reactions are increasing the applicability of ERH in environmental restoration projects, treating a wider variety of compounds and utilizing biotic and abiotic mechanisms to reduce energy costs. For the treatment of oil and coal tar residues from manufactured gas plants, a process TRS has called steam bubble floatation is used to physically remove the coal and oil tar from the soils for collection using conventional multi-phase collection methods. Heat-enhanced hydrolysis has been used to remediate dichloromethane from soils and groundwater at a site in Illinois, while heat-enhanced biotic and

  11. Advanced Electricity. Microprocessors and Robotics. Curriculum Development. Bulletin 1803.

    ERIC Educational Resources Information Center

    Southeastern Louisiana Univ., Hammond.

    This model instructional unit was developed to aid industrial arts/technology education teachers in Louisiana to teach a course on microprocessors and robotics in grades 11 and 12. It provides guidance on model performance objectives, current technology content, sources, and supplemental materials. Following a course description, rationale, and…

  12. Novel particle and radiation sources and advanced materials

    NASA Astrophysics Data System (ADS)

    Mako, Frederick

    2016-03-01

    The influence Norman Rostoker had on the lives of those who had the pleasure of knowing him is profound. The skills and knowledge I gained as a graduate student researching collective ion acceleration has fueled a career that has evolved from particle beam physics to include particle and radiation source development and advanced materials research, among many other exciting projects. The graduate research performed on collective ion acceleration was extended by others to form the backbone for laser driven plasma ion acceleration. Several years after graduate school I formed FM Technologies, Inc., (FMT), and later Electron Technologies, Inc. (ETI). Currently, as the founder and president of both FMT and ETI, the Rostoker influence can still be felt. One technology that we developed is a self-bunching RF fed electron gun, called the Micro-Pulse Gun (MPG). The MPG has important applications for RF accelerators and microwave tube technology, specifically clinically improved medical linacs and "green" klystrons. In addition to electron beam and RF source research, knowledge of materials and material interactions gained indirectly in graduate school has blossomed into breakthroughs in materials joining technologies. Most recently, silicon carbide joining technology has been developed that gives robust helium leak tight, high temperature and high strength joints between ceramic-to-ceramic and ceramic-to-metal. This joining technology has the potential to revolutionize the ethylene production, nuclear fuel and solar receiver industries by finally allowing for the practical use of silicon carbide as furnace coils, fuel rods and solar receptors, respectively, which are applications that have been needed for decades.

  13. Advances in materials for room temperature hydrogen sensors.

    PubMed

    Arya, Sunil K; Krishnan, Subramanian; Silva, Hayde; Jean, Sheila; Bhansali, Shekhar

    2012-06-21

    Hydrogen (H(2)), as a source of energy, continues to be a compelling choice in applications ranging from fuel cells and propulsion systems to feedstock for chemical, metallurgical and other industrial processes. H(2), being a clean, reliable, and affordable source, is finding ever increasing use in distributed electric power generation and H(2) fuelled cars. Although still under 0.1%, the distributed use of H(2) is the fastest growing area. In distributed H(2) storage, distribution, and consumption, safety continues to be a critical aspect. Affordable safety systems for distributed H(2) applications are critical for the H(2) economy to take hold. Advances in H(2) sensors are driven by specificity, reliability, repeatability, stability, cost, size, response time, recovery time, operating temperature, humidity range, and power consumption. Ambient temperature sensors for H(2) detection are increasingly being explored as they offer specificity, stability and robustness of high temperature sensors with lower operational costs and significantly longer operational lifetimes. This review summarizes and highlights recent developments in room temperature H(2) sensors. PMID:22582176

  14. Advanced batteries for electric vehicle applications: Nontechnical summary

    NASA Astrophysics Data System (ADS)

    Henriksen, G. L.

    This paper provides an overview of the performance characteristics of the most prominent batteries under development for electric vehicles (EV's) and compares these characteristics to the USABC Mid-Term and Long-Term criteria, as well as to typical vehicle-related battery requirements. Most of the battery performance information was obtained from independent tests, conducted using simulated driving power profiles, for DOE and EPRI at Argonne National Laboratory. The EV batteries are categorized as near-term, mid-term, and long-term technologies based on their relative development status, as well as our estimate of their potential availability as commercial EV batteries. Also, the performance capabilities generally increase in going from the near-term to the mid-term and on to the long-term technologies. To date, the USABC has chosen to fund a few selected mid-term and long-term battery technologies.

  15. Multiscale and Multiphysics Modeling of Additive Manufacturing of Advanced Materials

    NASA Technical Reports Server (NTRS)

    Liou, Frank; Newkirk, Joseph; Fan, Zhiqiang; Sparks, Todd; Chen, Xueyang; Fletcher, Kenneth; Zhang, Jingwei; Zhang, Yunlu; Kumar, Kannan Suresh; Karnati, Sreekar

    2015-01-01

    The objective of this proposed project is to research and develop a prediction tool for advanced additive manufacturing (AAM) processes for advanced materials and develop experimental methods to provide fundamental properties and establish validation data. Aircraft structures and engines demand materials that are stronger, useable at much higher temperatures, provide less acoustic transmission, and enable more aeroelastic tailoring than those currently used. Significant improvements in properties can only be achieved by processing the materials under nonequilibrium conditions, such as AAM processes. AAM processes encompass a class of processes that use a focused heat source to create a melt pool on a substrate. Examples include Electron Beam Freeform Fabrication and Direct Metal Deposition. These types of additive processes enable fabrication of parts directly from CAD drawings. To achieve the desired material properties and geometries of the final structure, assessing the impact of process parameters and predicting optimized conditions with numerical modeling as an effective prediction tool is necessary. The targets for the processing are multiple and at different spatial scales, and the physical phenomena associated occur in multiphysics and multiscale. In this project, the research work has been developed to model AAM processes in a multiscale and multiphysics approach. A macroscale model was developed to investigate the residual stresses and distortion in AAM processes. A sequentially coupled, thermomechanical, finite element model was developed and validated experimentally. The results showed the temperature distribution, residual stress, and deformation within the formed deposits and substrates. A mesoscale model was developed to include heat transfer, phase change with mushy zone, incompressible free surface flow, solute redistribution, and surface tension. Because of excessive computing time needed, a parallel computing approach was also tested. In addition

  16. Advanced low emissions catalytic combustor program at General Electric

    NASA Technical Reports Server (NTRS)

    Dodds, W. J.

    1979-01-01

    The Advanced Low Emissions Catalytic Combustors Program (ALECC) is being undertaken to evaluate the feasibility of employing catalytic combustion technology in aircraft gas turbine engines as a means to control emission of oxides of nitrogen during subsonic stratospheric cruise operation. The ALECC Program is being conducted in three phases. The first phase, which was completed in November, 1978, consisted of a design study to identify catalytic combustor designs having the greatest potential to meet the emissions and performance goals specified. The primary emissions goal of this program was to obtain cruise NO emissions of less than 1g/kg (compared with levels of 15 to 20 g/x obtained with current designs)/ However, good overall performance and feasibility for engine development were heavily weighted in the evaluation of combustor designs.

  17. Pluto/Kuiper Missions with Advanced Electric Propulsion and Power

    NASA Technical Reports Server (NTRS)

    Oleson, S. R.; Patterson, M. J.; Schrieber, J.; Gefert, L. P.

    2001-01-01

    In response to a request by NASA Code SD Deep Space Exploration Technology Program, NASA Glenn Research center performed a study to identify advanced technology options to perform a Pluto/Kuiper mission without depending on a 2004 Jupiter Gravity Assist, but still arriving before 2020. A concept using a direct trajectory with small, sub-kilowatt ion thrusters and Stirling radioisotope power system was shown to allow the same or smaller launch vehicle class (EELV) as the chemical 2004 baseline and allow launch in any year and arrival in the 2014 to 2020 timeframe. With the nearly constant power available from the radioisotope power source such small ion propelled spacecraft could explore many of the outer planetary targets. Such studies are already underway. Additional information is contained in the original extended abstract.

  18. Advanced materials based on carbon nanotube arrays, yarns and papers

    NASA Astrophysics Data System (ADS)

    Bradford, Phlip David

    Carbon nanotubes have hundreds of potential applications but require innovative processing techniques to manipulate the microscopic carbon dust into useful devices and products. This thesis describes efforts to process carbon nanotubes (CNTs) using novel methods with the goals of: (1) improving the properties of energy absorbing and composite carbon nanotube materials and (2) increasing understanding of fundamental structure-property relationships within these materials. Millimeter long CNTs, in the form of arrays, yarns and papers, were used to produce energy absorbing foams and high volume fraction CNT composites. Vertically aligned CNT arrays were grown on silicon substrates using chemical vapor deposition (CVD) of ethylene gas over iron nano-particles. The low density, millimeter thick arrays were tested under compression as energy absorbing foams. With additional CVD processing steps, it was possible to tune the compressive properties of the arrays. After the longest treatment, the compressive strength of the arrays was increased by a factor of 35 with a density increase of only six fold, while also imparting recovery from compression to the array. Microscopy revealed that the post-synthesis CVD treatment increased the number of CNT walls through an epitaxial type radial growth on the surface of the as-grown tubes. The increase in tube radius and mutual support between nanotubes explained the increases in compressive strength while an increase in nanotube roughness was proposed as the morphological change responsible for recovery in the array. Carbon nanotube yarns were used as the raw material for macroscopic textile preforms with a multi-level hierarchical carbon nanotube (CNT) structure: nanotubes, bundles, spun single yarns, plied yarns and 3-D braids. In prior tensile tests, composites produced from the 3-D braids exhibited unusual mechanical behavior effects. The proposed physical hypotheses explained those effects by molecular level interactions and

  19. Characterization and Application of Colloidal Nanocrystalline Materials for Advanced Photovoltaics

    NASA Astrophysics Data System (ADS)

    Bhandari, Khagendra P.

    Solar energy is Earth's primary source of renewable energy and photovoltaic solar cells enable the direct conversion of sunlight into electricity. Crystalline silicon solar cells and modules have dominated photovoltaic technology from the beginning and they now constitute more than 90% of the PV market. Thin film (CdTe and CIGS) solar cells and modules come in second position in market share. Some organic, dye-sensitized and perovskite solar cells are emerging in the market but are not yet in full commercial scale. Solar cells made from colloidal nanocrystalline materials may eventually provide both low cost and high efficiency because of their promising properties such as high absorption coefficient, size tunable band gap, and quantum confinement effect. It is also expected that the greenhouse gas emission and energy payback time from nanocrystalline solar PV systems will also be least compared to all other types of PV systems mainly due to the least embodied energy throughout their life time. The two well-known junction architectures for the fabrication of quantum dot based photovoltaic devices are the Schottky junction and heterojunction. In Schottky junction cells, a heteropartner semiconducting material is not required. A low work function metal is used as the back contact, a transparent conducting layer is used as the front contact, and the layer of electronically-coupled quantum dots is placed between these two materials. Schottky junction solar cells explain the usefulness of nanocrystalline materials for high efficiency heterojunction solar cells. For heterojunction devices, n-type semiconducting materials such as ZnO , CdS or TiO2 have been used as suitable heteropartners. Here, PbS quantum dot solar cells were fabricated using ZnO and CdS semiconductor films as window layers. Both of the heteropartners are sputter-deposited onto TCO coated glass substrates; ZnO was deposited with the substrate held at room temperature and for CdS the substrate was at 250

  20. Advanced gas turbines: The choice for low-cost, environmentally superior electric power generation

    SciTech Connect

    Zeh, C.M.

    1996-08-01

    In July 1993, the US Department of Energy (DOE) initiated an ambitious 8-year program to advance state-of-the-art gas turbine technology for land-based electric power generation. The program, known as the Advanced Turbine System (ATS) Program, is a joint government/industry program with the objective to demonstrate advanced industrial and utility gas turbine systems by the year 2000. The goals of the ATS Program are to develop gas turbine systems capable of providing low-cost electric power, while maintaining environmental superiority over competing power generation options. A progress report on the ATS Program pertaining to program status at DOE will be presented and reviewed in this paper. The technical challenges, advanced critical technology requirements, and systems designs meeting the goals of the program will be described and discussed.

  1. Experimental and computing strategies in advanced material characterization problems

    NASA Astrophysics Data System (ADS)

    Bolzon, G.

    2015-10-01

    The mechanical characterization of materials relies more and more often on sophisticated experimental methods that permit to acquire a large amount of data and, contemporarily, to reduce the invasiveness of the tests. This evolution accompanies the growing demand of non-destructive diagnostic tools that assess the safety level of components in use in structures and infrastructures, for instance in the strategic energy sector. Advanced material systems and properties that are not amenable to traditional techniques, for instance thin layered structures and their adhesion on the relevant substrates, can be also characterized by means of combined experimental-numerical tools elaborating data acquired by full-field measurement techniques. In this context, parameter identification procedures involve the repeated simulation of the laboratory or in situ tests by sophisticated and usually expensive non-linear analyses while, in some situation, reliable and accurate results would be required in real time. The effectiveness and the filtering capabilities of reduced models based on decomposition and interpolation techniques can be profitably used to meet these conflicting requirements. This communication intends to summarize some results recently achieved in this field by the author and her co-workers. The aim is to foster further interaction between engineering and mathematical communities.

  2. Experimental and computing strategies in advanced material characterization problems

    SciTech Connect

    Bolzon, G.

    2015-10-28

    The mechanical characterization of materials relies more and more often on sophisticated experimental methods that permit to acquire a large amount of data and, contemporarily, to reduce the invasiveness of the tests. This evolution accompanies the growing demand of non-destructive diagnostic tools that assess the safety level of components in use in structures and infrastructures, for instance in the strategic energy sector. Advanced material systems and properties that are not amenable to traditional techniques, for instance thin layered structures and their adhesion on the relevant substrates, can be also characterized by means of combined experimental-numerical tools elaborating data acquired by full-field measurement techniques. In this context, parameter identification procedures involve the repeated simulation of the laboratory or in situ tests by sophisticated and usually expensive non-linear analyses while, in some situation, reliable and accurate results would be required in real time. The effectiveness and the filtering capabilities of reduced models based on decomposition and interpolation techniques can be profitably used to meet these conflicting requirements. This communication intends to summarize some results recently achieved in this field by the author and her co-workers. The aim is to foster further interaction between engineering and mathematical communities.

  3. Material morphology and electrical resistivity differences in EPDM rubbers.

    SciTech Connect

    Yang, Nancy Y. C.; Domeier, Linda A.

    2008-03-01

    Electrical resistance anomalies noted in EPDM gaskets have been attributed to zinc-enriched surface sublayers, about 10-{micro}m thick, in the sulfur cured rubber material. Gasket over-compression provided the necessary connector pin contact and was also found to cause surprising morphological changes on the gasket surfaces. These included distributions of zinc oxide whiskers in high pressure gasket areas and cone-shaped features rich in zinc, oxygen, and sulfur primarily in low pressure protruding gasket areas. Such whiskers and cones were only found on the pin side of the gaskets in contact with a molded plastic surface and not on the back side in contact with an aluminum surface. The mechanisms by which such features are formed have not yet been defined.

  4. Research on lunar materials. [optical, chemical, and electrical properties

    NASA Technical Reports Server (NTRS)

    Gold, T.

    1978-01-01

    Abstracts of 14 research reports relating to investigations of lunar samples are presented. The principal topics covered include: (1) optical properties of surface and core samples; (2) chemical composition of the surface layers of lunar grains: Auger electron spectroscopy of lunar soil and ground rock samples; (3) high frequency electrical properties of lunar soil and rock samples and their relevance for the interpretation of lunar radar observations; (4) the electrostatic dust transport process; (5) secondary electron emission characteristics of lunar soil samples and their relevance to the dust transportation process; (6) grain size distribution in surface soil and core samples; and (7) the optical and chemical effects of simulated solar wind (2keV proton and a particle radiation) on lunar material.

  5. Nitrogen-doped porous graphitic carbon as an excellent electrode material for advanced supercapacitors.

    PubMed

    Sun, Li; Tian, Chungui; Fu, Yu; Yang, Ying; Yin, Jie; Wang, Lei; Fu, Honggang

    2014-01-01

    An advanced supercapacitor material based on nitrogen-doped porous graphitic carbon (NPGC) with high a surface area was synthesized by means of a simple coordination-pyrolysis combination process, in which tetraethyl orthosilicate (TEOS), nickel nitrate, and glucose were adopted as porogent, graphitic catalyst precursor, and carbon source, respectively. In addition, melamine was selected as a nitrogen source owing to its nitrogen-enriched structure and the strong interaction between the amine groups and the glucose unit. A low-temperature treatment resulted in the formation of a NPGC precursor by combination of the catalytic precursor, hydrolyzed TEOS, and the melamine-glucose unit. Following pyrolysis and removal of the catalyst and porogent, the NPGC material showed excellent electrical conductivity owing to its high crystallinity, a large Brunauer-Emmett-Teller surface area (SBET =1027 m(2)  g(-1) ), and a high nitrogen level (7.72 wt %). The unusual microstructure of NPGC materials could provide electrochemical energy storage. The NPGC material, without the need for any conductive additives, showed excellent capacitive behavior (293 F g(-1) at 1 A g(-1) ), long-term cycling stability, and high coulombic efficiency (>99.9 % over 5000 cycles) in KOH when used as an electrode. Notably, in a two-electrode symmetric supercapacitor, NPGC energy densities as high as 8.1 and 47.5 Wh kg(-1) , at a high power density (10.5 kW kg(-1) ), were achieved in 6 M KOH and 1 M Et4 NBF4 -PC electrolytes, respectively. Thus, the synthesized NPGC material could be a highly promising electrode material for advanced supercapacitors and other conversion devices. PMID:24307432

  6. Program for the development of high temperature electrical materials and components

    NASA Technical Reports Server (NTRS)

    Neff, W. S.; Lowry, L. R.

    1972-01-01

    Evaluation of high temperature, space-vacuum performance of selected electrical materials and components, high temperature capacitor development, and evaluation, construction, and endurance testing of compression sealed pyrolytic boron nitride slot insulation are described. The first subject above covered the aging evaluation of electrical devices constructed from selected electrical materials. Individual materials performances were also evaluated and reported. The second subject included study of methods of improving electrical performance of pyrolytic boron nitride capacitors. The third portion was conducted to evaluate the thermal and electrical performance of pyrolytic boron nitride as stator slot liner material under varied temperature and compressive loading. Conclusions and recommendations are presented.

  7. Design options for automotive batteries in advanced car electrical systems

    NASA Astrophysics Data System (ADS)

    Peters, K.

    The need to reduce fuel consumption, minimize emissions, and improve levels of safety, comfort and reliability is expected to result in a much higher demand for electric power in cars within the next 5 years. Forecasts vary, but a fourfold increase in starting power to 20 kW is possible, particularly if automatic stop/start features are adopted to significantly reduce fuel consumption and exhaust emissions. Increases in the low-rate energy demand are also forecast, but the use of larger alternators may avoid unacceptable high battery weights. It is also suggested from operational models that the battery will be cycled more deeply. In examining possible designs, the beneficial features of valve-regulated lead-acid batteries made with compressed absorbent separators are apparent. Several of their attributes are considered. They offer higher specific power, improved cycling capability and greater vibration resistance, as well as more flexibility in packaging and installation. Optional circuits considered for dual-voltage supplies are separate batteries for engine starting (36 V) and low-power duties (12 V), and a universal battery (36 V) coupled to a d.c.-d.c. converter for a 12-V equipment. Battery designs, which can be made on commercially available equipment with similar manufacturing costs (per W h and per W) to current products, are discussed. The 36-V battery, made with 0.7 mm thick plates, in the dual-battery system weighs 18.5 kg and has a cold-cranking amp (CCA) rating of 790 A at -18°C to 21.6 V (1080 W kg -1 at a mean voltage of 25.4 V). The associated, cycleable 12-V battery, provides 1.5 kW h and weighs 24.6 kg. Thus, the combined battery weight is 43.1 kg. The single universal battery, with cycling capability, weighs 45.4 kg, has a CCA rating of 810 A (441 W kg -1 at a mean voltage of 24.7 V), and when connected to the d.c.-d.c. converter at 75% efficiency provides a low-power capacity of 1.5 kW h.

  8. High-Tc superconducting materials for electric power applications.

    PubMed

    Larbalestier, D; Gurevich, A; Feldmann, D M; Polyanskii, A

    2001-11-15

    Large-scale superconducting electric devices for power industry depend critically on wires with high critical current densities at temperatures where cryogenic losses are tolerable. This restricts choice to two high-temperature cuprate superconductors, (Bi,Pb)2Sr2Ca2Cu3Ox and YBa2Cu3Ox, and possibly to MgB2, recently discovered to superconduct at 39 K. Crystal structure and material anisotropy place fundamental restrictions on their properties, especially in polycrystalline form. So far, power applications have followed a largely empirical, twin-track approach of conductor development and construction of prototype devices. The feasibility of superconducting power cables, magnetic energy-storage devices, transformers, fault current limiters and motors, largely using (Bi,Pb)2Sr2Ca2Cu3Ox conductor, is proven. Widespread applications now depend significantly on cost-effective resolution of fundamental materials and fabrication issues, which control the production of low-cost, high-performance conductors of these remarkable compounds. PMID:11713544

  9. Advanced electric propulsion and space plasma contactor research

    NASA Technical Reports Server (NTRS)

    Wilbur, P. J.

    1986-01-01

    A series of experiments performed on an 8 cm dia. ring cusp magnetic field ion thruster are described. The results show the effects of anode and cathode position and size, ring cusp axial location and discharge chamber length on plasma ion energy cost and extracted ion fraction. Thruster performance is shown to be improved substantially when optimum values of these parameters are used. Investigations into the basic plasma phenomena associated with the process of plasma contacting are described. The results show the process of electron collection from a background plasma to a hollow cathode plasma contactor exhibits a higher impedance than the process of electron emission from the hollow cathode. The importance of having cold ions present to facilitate the plasma contacting process is shown. Results of experiments into the behavior of hollow cathodes operating at high interelectrode pressures (up to approx. 100 Torr) on nitrogen and ammonia are presented. They suggest that diffuse emission from the insert of a hollow cathode can be sustained at high interelectrode pressures if the cathode is made of non-conducting material and the cathode internal pressure is reduced by evacuating the cathode interior. A theoretical model of discharge chamber operation developed for inert gas thrusters is extended so it can be used to evaluste the performance of mercury ion thrusters. Predictions of the model are compared to experimental results obtained on two 30 cm dia. thrusters.

  10. Thermoelectric materials by using two-dimensional materials with negative correlation between electrical and thermal conductivity

    NASA Astrophysics Data System (ADS)

    Lee, Myoung-Jae; Ahn, Ji-Hoon; Sung, Ji Ho; Heo, Hoseok; Jeon, Seong Gi; Lee, Woo; Song, Jae Yong; Hong, Ki-Ha; Choi, Byeongdae; Lee, Sung-Hoon; Jo, Moon-Ho

    2016-06-01

    In general, in thermoelectric materials the electrical conductivity σ and thermal conductivity κ are related and thus cannot be controlled independently. Previously, to maximize the thermoelectric figure of merit in state-of-the-art materials, differences in relative scaling between σ and κ as dimensions are reduced to approach the nanoscale were utilized. Here we present an approach to thermoelectric materials using tin disulfide, SnS2, nanosheets that demonstrated a negative correlation between σ and κ. In other words, as the thickness of SnS2 decreased, σ increased whereas κ decreased. This approach leads to a thermoelectric figure of merit increase to 0.13 at 300 K, a factor ~1,000 times greater than previously reported bulk single-crystal SnS2. The Seebeck coefficient obtained for our two-dimensional SnS2 nanosheets was 34.7 mV K-1 for 16-nm-thick samples at 300 K.

  11. Effects of Oxide-Modified Spherical ZnO on Electrical Properties of Ag/ZnO Electrical Contact Material

    NASA Astrophysics Data System (ADS)

    Wei, Zhijun; Zhang, Lingjie; Shen, Tao; Qiao, Zhengyang; Yang, Hui; Fan, Xianping; Chen, Lawson

    2016-07-01

    Silver-zinc oxide (Ag/ZnO) electrical contact material is widely used as contacts of the medium duty switching devices. Effects of modified ZnO on properties of Ag/ZnO electrical contact material were investigated in this work. NiO and CuO were introduced to modify spherical ZnO by a chemical solution nano-coating method. Ag/ZnO contacts prepared using the modified spherical ZnO were produced by powder metallurgy (PM) method in a muffle furnace in temperature ranges from 750 to 900 °C. Results show that electrical conductivity, stability of relative density, and Vickers' hardness of Ag/ZnO electrical contact material can be improved by the addition of NiO because of the formation of NiO solid solution Zn0.2Ni0.8O. The addition of CuO to Ag/ZnO electrical contact material makes arcing energy and mass loss lower. Since this is attractive for a longer service life, using NiO and CuO co-modified ZnO as a second phase may be a promising way to improve properties of Ag/ZnO electrical contact material. Hence, the presented results could also be useful for the design of a new Ag/ZnO electrical contact material.

  12. New developments on valve-regulated lead-acid batteries for advanced automotive electrical systems

    NASA Astrophysics Data System (ADS)

    Soria, M. L.; Hernández, J. C.; Valenciano, J.; Sánchez, A.; Trinidad, F.

    The development of novel electrical systems for low emission vehicles demands batteries with specific cycling performance, especially under partial state of charge (PSOC) conditions. Moreover, according to the powertrain design, battery high power capability is demanded or this function can be assumed by a supercapacitor or a flywheel. This paper deals with the development of AGM and gel valve-regulated lead-acid batteries for advanced automotive applications. AGM VRLA battery development was based on previous work for short autonomy high power UPS applications and on active material formulations with specific additives to improve battery life under high rate partial state of charge cycling conditions. The 18 Ah batteries showed excellent high rate capability (9 kW 10 s discharge peaks and 4 kW 5 s regenerative charge acceptance at 60% state of charge) and 110,000 power assist microcycles at 60% SOC and 2.5% DOD were fulfilled. Moreover, as preliminary work in the development of a cost-effective and reliable gel battery to be used in combination of a supercapacitor in a 42 V mild-hybrid powertrain, VRLA batteries with conventional gel formulations have been tested according to novel automotive cycling profiles, mainly moderate cycling under partial state of charge conditions and simulating load management in a stop and start working profile.

  13. Composite Materials with Magnetically Aligned Carbon Nanoparticles Having Enhanced Electrical Properties and Methods of Preparation

    NASA Technical Reports Server (NTRS)

    Hong, Haiping (Inventor); Peterson, G.P. (Bud) (Inventor); Salem, David R. (Inventor)

    2016-01-01

    Magnetically aligned carbon nanoparticle composites have enhanced electrical properties. The composites comprise carbon nanoparticles, a host material, magnetically sensitive nanoparticles and a surfactant. In addition to enhanced electrical properties, the composites can have enhanced mechanical and thermal properties.

  14. Electric Ground Support Equipment Advanced Battery Technology Demonstration Project at the Ontario Airport

    SciTech Connect

    Tyler Gray; Jeremy Diez; Jeffrey Wishart; James Francfort

    2013-07-01

    The intent of the electric Ground Support Equipment (eGSE) demonstration is to evaluate the day-to-day vehicle performance of electric baggage tractors using two advanced battery technologies to demonstrate possible replacements for the flooded lead-acid (FLA) batteries utilized throughout the industry. These advanced battery technologies have the potential to resolve barriers to the widespread adoption of eGSE deployment. Validation testing had not previously been performed within fleet operations to determine if the performance of current advanced batteries is sufficient to withstand the duty cycle of electric baggage tractors. This report summarizes the work performed and data accumulated during this demonstration in an effort to validate the capabilities of advanced battery technologies. This report summarizes the work performed and data accumulated during this demonstration in an effort to validate the capabilities of advanced battery technologies. The demonstration project also grew the relationship with Southwest Airlines (SWA), our demonstration partner at Ontario International Airport (ONT), located in Ontario, California. The results of this study have encouraged a proposal for a future demonstration project with SWA.

  15. Using advanced electron microscopy for the characterization of catalytic materials

    NASA Astrophysics Data System (ADS)

    Pyrz, William D.

    Catalysis will continue to be vitally important to the advancement and sustainability of industrialized societies. Unfortunately, the petroleum-based resources that currently fuel the energy and consumer product needs of an advancing society are becoming increasingly difficult and expensive to extract as supplies diminish and the quality of sources degrade. Therefore, the development of sustainable energy sources and the improvement of the carbon efficiency of existing chemical processes are critical. Further challenges require that these initiatives are accomplished in an environmentally friendly fashion since the effects of carbon-based emissions are proving to be a serious threat to global climate stability. In this dissertation, materials being developed for sustainable energy and process improvement initiatives are studied. Our approach is to use materials characterization, namely advanced electron microscopy, to analyze the targeted systems at the nano- or Angstrom-scale with the goal of developing useful relationships between structure, composition, crystalline order, morphology, and catalytic performance. One area of interest is the complex Mo-V-M-O (M=Te, Sb, Ta, Nb) oxide system currently being developed for the selective oxidation/ammoxidation of propane to acrylic acid or acrylonitrile, respectively. Currently, the production of acrylic acid and acrylonitrile rely on propylene-based processes, yet significant cost savings could be realized if the olefin-based feeds could be replaced by paraffin-based ones. The major challenge preventing this feedstock replacement is the development of a suitable paraffin-activating catalyst. Currently, the best candidate is the Mo-V-Nb-Te-O complex oxide catalyst that is composed of two majority phases that are commonly referred to as M1 and M2. However, there is a limited understanding of the roles of each component with respect to how they contribute to catalyst stability and the reaction mechanism. Aberration

  16. A chemistry and material perspective on lithium redox flow batteries towards high-density electrical energy storage.

    PubMed

    Zhao, Yu; Ding, Yu; Li, Yutao; Peng, Lele; Byon, Hye Ryung; Goodenough, John B; Yu, Guihua

    2015-11-21

    Electrical energy storage system such as secondary batteries is the principle power source for portable electronics, electric vehicles and stationary energy storage. As an emerging battery technology, Li-redox flow batteries inherit the advantageous features of modular design of conventional redox flow batteries and high voltage and energy efficiency of Li-ion batteries, showing great promise as efficient electrical energy storage system in transportation, commercial, and residential applications. The chemistry of lithium redox flow batteries with aqueous or non-aqueous electrolyte enables widened electrochemical potential window thus may provide much greater energy density and efficiency than conventional redox flow batteries based on proton chemistry. This Review summarizes the design rationale, fundamentals and characterization of Li-redox flow batteries from a chemistry and material perspective, with particular emphasis on the new chemistries and materials. The latest advances and associated challenges/opportunities are comprehensively discussed. PMID:26265165

  17. Recent Advances in Conjugated Polymer Materials for Disease Diagnosis.

    PubMed

    Lv, Fengting; Qiu, Tian; Liu, Libing; Ying, Jianming; Wang, Shu

    2016-02-10

    The extraordinary optical amplification and light-harvesting properties of conjugated polymers impart sensing systems with higher sensitivity, which meets the primary demands of early cancer diagnosis. Recent advances in the detection of DNA methylation and mutation with polyfluorene derivatives based fluorescence resonance energy transfer (FRET) as a means to modulate fluorescent responses attest to the great promise of conjugated polymers as powerful tools for the clinical diagnosis of diseases. To facilitate the ever-changing needs of diagnosis, the development of detection approaches and FRET signal analysis are highlighted in this review. Due to their exceptional brightness, excellent photostability, and low or absent toxicity, conjugated polymers are verified as superior materials for in-vivo imaging, and provide feasibility for future clinical molecular-imaging applications. The integration of conjugated polymers with clinical research has shown profound effects on diagnosis for the early detection of disease-related biomarkers, as well as in-vivo imaging, which leads to a multidisciplinary scientific field with perspectives in both basic research and application issues. PMID:26679834

  18. Economics of co-firing waste materials in an advanced pressurized fluidized-bed combustor

    SciTech Connect

    Bonk, D.L.; McDaniel, H.M.; DeLallo, M.R. Jr.; Zaharchuk, R.

    1995-04-01

    The co-firing of waste materials with coal in utility scale power plants has emerged as an effective approach to produce energy and manage municipal waste. Leading this approach is the atmospheric fluidized bed combustor (AFBC). It has demonstrated its commercial acceptance in the utility market as a reliable source of power by burning a variety of waste and alternative fuels. The fluidized bed, with its stability of combustion, reduces the amount of thermochemical transients and provides for easier process control. The application of pressurized fluidized-bed combustor (PFBC) technology, although relatively new, can provide significant enhancements to the efficient production of electricity while maintaining the waste management benefits of AFBC. A study was undertaken to investigate the technical and economic feasibility of co-firing a PFBC with coal and municipal and industrial wastes. Focus was placed on the production of electricity and the efficient disposal of wastes for application in central power station and distributed locations. Issues concerning waste material preparation and feed, PFBC operation, plant emissions, and regulations are addressed. The results and conclusions developed are generally applicable to current and advanced PFBC design concepts.

  19. Mission Concepts Enabled by Solar Electric Propulsion and Advanced Modular Power Systems

    NASA Astrophysics Data System (ADS)

    Klaus, Kurt K.; Elsperman, M. S.; Rogers, F.

    2013-10-01

    Introduction: Over the last several years we have introduced a number of planetary mission concepts enabled by Solar Electric Propulsion and Advanced Modular Power systems. The Boeing 702 SP: Using a common spacecraft for multiple missions reduces costs. Solar electric propulsion (SEP) provides the flexibility required for multiple mission objectives. Hosted payloads allow launch and operations costs to be shared. Advanced Modular Power System (AMPS): The 702 SP for deep space is designed to be able to use the Advanced Modular Power System (AMPS) solar array, producing multi Kw power levels with significantly lower system mass than current solar power system technologies. Mission Concepts: Outer Planets. 1) Europa Explorer - Our studies demonstrate that New Frontiers-class science missions to the Jupiter and Saturn systems are possible with commercial solar powered spacecraft. 2) Trojan Tour -The mission objective is 1143 Odysseus, consistent with the Decadal Survey REP (Radioisotope Electric Propulsion) mission objective. Small Body. 1) NEO Precursor Mission - NEO missions benefit greatly by using high ISP (Specific Impulse) Solar Electric Propulsion (SEP) coupled with high power generation systems. This concept further sets the stage for human exploration by doing the type of science exploration needed and flight demonstrating technology advances (high power generation, SEP). 2) Multiple NEO Rendezvous, Reconnaissance and In Situ Exploration - We propose a two spacecraft mission (Mother Ship and Small Body Lander) rendezvous with multiple Near Earth Objects (NEO). Mars. Our concept involved using the Boeing 702SP with a highly capable SAR imager that also conducts autonomous rendezvous and docking experiments accomplished from Mars orbit. Conclusion: Using advanced in-space power and propulsion technologies like High Power Solar Electric Propulsion provides enormous mission flexibility to execute baseline science missions and conduct Technology Demonstrations in

  20. Mission Concepts Enabled by Solar Electric Propulsion and Advanced Modular Power Systems

    NASA Astrophysics Data System (ADS)

    Elsperman, M. S.; Klaus, K.; Rogers, F.

    2013-12-01

    Introduction: Over the last several years we have introduced a number of planetary mission concepts enabled by Solar Electric Propulsion and Advanced Modular Power systems. The Boeing 702 SP: Using a common spacecraft for multiple missions reduces costs. Solar electric propulsion (SEP) provides the flexibility required for multiple mission objectives. Hosted payloads allow launch and operations costs to be shared. Advanced Modular Power System (AMPS): The 702 SP for deep space is designed to be able to use the Advanced Modular Power System (AMPS) solar array, producing multi Kw power levels with significantly lower system mass than current solar power system technologies. Mission Concepts: Outer Planets. 1) Europa Explorer - Our studies demonstrate that New Frontiers-class science missions to the Jupiter and Saturn systems are possible with commercial solar powered spacecraft. 2) Trojan Tour -The mission objective is 1143 Odysseus, consistent with the Decadal Survey REP (Radioisotope Electric Propulsion) mission objective. Small Body. 1) NEO Precursor Mission - NEO missions benefit greatly by using high ISP (Specific Impulse) Solar Electric Propulsion (SEP) coupled with high power generation systems. This concept further sets the stage for human exploration by doing the type of science exploration needed and flight demonstrating technology advances (high power generation, SEP). 2) Multiple NEO Rendezvous, Reconnaissance and In Situ Exploration - We propose a two spacecraft mission (Mother Ship and Small Body Lander) rendezvous with multiple Near Earth Objects (NEO). Mars. Our concept involved using the Boeing 702SP with a highly capable SAR imager that also conducts autonomous rendezvous and docking experiments accomplished from Mars orbit. Conclusion: Using advanced in-space power and propulsion technologies like High Power Solar Electric Propulsion provides enormous mission flexibility to execute baseline science missions and conduct Technology Demonstrations in

  1. Recent advances in the molten salt destruction of energetic materials

    SciTech Connect

    Pruneda, C. O., LLNL

    1996-09-01

    We have demonstrated the use of the Molten Salt Destruction (MSD) Process for destroying explosives, liquid gun propellant, and explosives-contaminated materials on a 1.5 kg of explosive/hr bench- scale unit (1, 2, 3, 4, 5). In our recently constructed 5 kg/hr pilot- scale unit we have also demonstrated the destruction of a liquid gun propellant and simulated wastes containing HMX (octogen). MSD converts the organic constituents of the waste into non-hazardous substances such as carbon dioxide, nitrogen, and water. Any inorganic constituents of the waste, such as metallic particles, are retained in the molten salt. The destruction of energetic materials waste is accomplished by introducing it, together with air, into a vessel containing molten salt (a eutectic mixture of sodium, potassium, and lithium carbonates). The following pure explosives have been destroyed in our bench-scale experimental unit located at Lawrence Livermore National Laboratory`s (LLNL) High Explosives Applications Facility (HEAF): ammonium picrate, HMX, K- 6 (keto-RDX), NQ, NTO, PETN, RDX, TATB, and TNT. In addition, the following compositions were also destroyed: Comp B, LX- IO, LX- 1 6, LX- 17, PBX-9404, and XM46 (liquid gun propellant). In this 1.5 kg/hr bench-scale unit, the fractions of carbon converted to CO and of chemically bound nitrogen converted to NO{sub x} were found to be well below 1%. In addition to destroying explosive powders and compositions we have also destroyed materials that are typical of residues which result from explosives operations. These include shavings from machined pressed parts of plastic-bonded explosives and sump waste containing both explosives and non-explosive debris. Based on the process data obtained on the bench-scale unit we designed and constructed a next-generation 5 kg/hr pilot-scale unit, incorporating LLNL`s advanced chimney design. The pilot unit has completed process implementation operations and explosives safety reviews. To date, in this

  2. Advanced propulsion concepts study: Comparative study of solar electric propulsion and laser electric propulsion

    NASA Technical Reports Server (NTRS)

    Forward, R. L.

    1975-01-01

    Solar electric propulsion (SEP) and laser electric propulsion (LEP) was compared. The LEP system configuration consists of an 80 kW visible laser source on earth, transmitting via an 8 m diameter adaptively controlled phased array through the atmosphere to a 4 m diameter synchronous relay mirror that tracks the LEP spacecraft. The only significant change in the SEP spacecraft for an LEP mission is the replacement of the two 3.7 m by 33.5 m solar cell arrays with a single 8 m diameter laser photovoltaic array. The solar cell array weight is decreased from 320 kg to 120 kg for an increase in payload of 200 kg and a decrease in specific mass of the power system from 20.5 kg/kW to 7.8 kg/kW.

  3. Some aspects of coupled electrical-mechanical effects in dielectric materials

    NASA Astrophysics Data System (ADS)

    Teyssedre, Gilbert; Berquez, Laurent; Laurent, Christian

    2015-05-01

    The propensity of electrically insulating materials to generate/store electrical charges leads to a panel of electromechanical phenomena that can be either exploited in applications relevant to electrical engineering, or represent limitations in the performance of insulating materials. The aim of this contribution is to describe various features of these electrical-mechanical coupling phenomena with focus on the field-induced strain measurement of charged polymers, on the charge distribution measurement by pulsed electroacoustic method and on the contribution of electromechanical effects in electrical ageing phenomena. Contribution to the topical issue "Electrical Engineering Symposium (SGE 2014)", edited by Adel Razek

  4. Advanced copper/low-k IC devices: Packaging process development and materials integrtion

    NASA Astrophysics Data System (ADS)

    Chungpaiboonpatana, Surasit

    Cu/low-k technology provides a number of key advantages including higher interconnect density, improved electrical performance, enhanced thermal performance, and reduced cost. Nevertheless, Cu/low-k IC technology poses many challenges to the packaging industry today. Specifically, low-k dielectric is much more fragile mechanically and copper surfaces are readily oxidized thereby weakening their adhesion to the ILD/metallization layers. The purpose of the study is to provide integrated and reliable materials and process solutions for the packaging of advanced Cu/low-k devices through fundamental materials science understanding. Novel solutions for advanced wirebond and flip-chip technologies are developed, along with resolutions for local and global material interaction issues. The zero-th packaging level study examines a novel direct gold wirebonding onto the Cu/low-k terminal pad structure. The first packaging level study attempts to eliminate the Cu/low-k wiresweeping issue through assembly material interactions with both bonding and transfer molding processes. The second packaging level study exams at the impact of Cu/low-k and processing material implementations on the copper trace cracking failures at the substrate level of a package. An integrated first and second level study on high performance flip chip technology using 8M Cu/low-k silicon chip is performed by the optimization of the underfill and substrate materials selections. Lastly, electromigration phenomena and corrosion mechanisms of copper metallization are developed for biased stressing assembly environment through the fundamental of electrochemistry. Throughout the experiment, the 90/130nm technology node of copper wafer fabrication using Black Diamond low-k dielectric is implemented in several large form-factor package assemblies. Functional test vehicles are assembled, reliability-stressed, and failure-analyzed according to the JEDEC standards for the validity of the integrated materials

  5. Advanced Materials for RSOFC Dual Operation with Low Degradation

    SciTech Connect

    Eric, Tang; Tony, Wood; Sofiane, Benhaddad; Casey, Brown; Hongpeng, He; Jeff, Nelson; Oliver, Grande; Ben, Nuttall; Mark, Richards; Randy, Petri

    2012-12-27

    Reversible solid oxide fuel cells (RSOFCs) are energy conversion devices. They are capable of operating in both power generation mode (SOFC) and electrolysis modes (SOEC). RSOFC can integrate renewable production of electricity and hydrogen when power generation and steam electrolysis are coupled in a system, which can turn intermittent solar and wind energy into "firm power." In this DOE EERE project, VPS continuously advanced RSOFC cell stack technology in the areas of endurance and performance. Over 20 types of RSOFC cells were developed in the project. Many of those exceeded performance (area specific resistance less than 300 mohmcm2) and endurance (degradation rate less than 4% per 1000 hours) targets in both fuel cell and electrolysis modes at 750C. One of those cells, RSOFC-7, further demonstrated the following: Steady-state electrolysis with a degradation rate of 1.5% per 1000 hours. Ultra high current electrolysis over 3 A/cm2 at 75% water electrolysis efficiency voltage of 1.67 V. Daily SOFC/SOEC cyclic test of over 600 days with a degradation rate of 1.5% per 1000 hours. Over 6000 SOFC/SOEC cycles in an accelerated 20-minute cycling with degradation less than 3% per 1000 cycles. In RSOFC stack development, a number of kW-class RSOFC stacks were developed and demonstrated the following: Steady-state electrolysis operation of over 5000 hours. Daily SOFC/SOEC cyclic test of 100 cycles. Scale up capability of using large area cells with 550 cm2 active area showing the potential for large-scale RSOFC stack development in the future. Although this project is an open-ended development project, this effort, leveraging Versa Power Systems' years of development experience, has the potential to bring renewable energy RSOFC storage systems significantly closer to commercial viability through improvements in RSOFC durability, performance, and cost. When unitized and deployed in renewable solar and wind installations, an RSOFC system can enable higher availability for

  6. Ultrathin coatings of nanoporous materials as property enhancements for advanced functional materials.

    SciTech Connect

    Coker, Eric Nicholas

    2010-11-01

    This report summarizes the findings of a five-month LDRD project funded through Sandia's NTM Investment Area. The project was aimed at providing the foundation for the development of advanced functional materials through the application of ultrathin coatings of microporous or mesoporous materials onto the surface of substrates such as silicon wafers. Prior art teaches that layers of microporous materials such as zeolites may be applied as, e.g., sensor platforms or gas separation membranes. These layers, however, are typically several microns to several hundred microns thick. For many potential applications, vast improvements in the response of a device could be realized if the thickness of the porous layer were reduced to tens of nanometers. However, a basic understanding of how to synthesize or fabricate such ultra-thin layers is lacking. This report describes traditional and novel approaches to the growth of layers of microporous materials on silicon wafers. The novel approaches include reduction of the quantity of nutrients available to grow the zeolite layer through minimization of solution volume, and reaction of organic base (template) with thermally-oxidized silicon wafers under a steam atmosphere to generate ultra-thin layers of zeolite MFI.

  7. Depleted uranium hexafluoride: The source material for advanced shielding systems

    SciTech Connect

    Quapp, W.J.; Lessing, P.A.; Cooley, C.R.

    1997-02-01

    The U.S. Department of Energy (DOE) has a management challenge and financial liability problem in the form of 50,000 cylinders containing 555,000 metric tons of depleted uranium hexafluoride (UF{sub 6}) that are stored at the gaseous diffusion plants. DOE is evaluating several options for the disposition of this UF{sub 6}, including continued storage, disposal, and recycle into a product. Based on studies conducted to date, the most feasible recycle option for the depleted uranium is shielding in low-level waste, spent nuclear fuel, or vitrified high-level waste containers. Estimates for the cost of disposal, using existing technologies, range between $3.8 and $11.3 billion depending on factors such as the disposal site and the applicability of the Resource Conservation and Recovery Act (RCRA). Advanced technologies can reduce these costs, but UF{sub 6} disposal still represents large future costs. This paper describes an application for depleted uranium in which depleted uranium hexafluoride is converted into an oxide and then into a heavy aggregate. The heavy uranium aggregate is combined with conventional concrete materials to form an ultra high density concrete, DUCRETE, weighing more than 400 lb/ft{sup 3}. DUCRETE can be used as shielding in spent nuclear fuel/high-level waste casks at a cost comparable to the lower of the disposal cost estimates. Consequently, the case can be made that DUCRETE shielded casks are an alternative to disposal. In this case, a beneficial long term solution is attained for much less than the combined cost of independently providing shielded casks and disposing of the depleted uranium. Furthermore, if disposal is avoided, the political problems associated with selection of a disposal location are also avoided. Other studies have also shown cost benefits for low level waste shielded disposal containers.

  8. ADVANCED GASIFICATION-BASED FUEL CONVERSION AND ELECTRIC ENERGY PRODUCTION SYSTEM

    SciTech Connect

    Joseph Rabovitser; Bruce Bryan

    2003-04-01

    The objective of this project is the development and commercial demonstration of an advanced biomass gasification-based power generation system at Boise Cascade Corporation's pulp and paper mill in DeRidder, Louisiana. The advanced power generation system is intended to meet the immediate needs of the forest products industry for highly efficient and environmentally friendly electricity and steam generation systems utilizing existing wood waste as the primary fuel resource. The novel system is based on three advanced technology components: GTI's RENUGAS{reg_sign} and 3-stage solid fuels combustion technologies coupled with one of the power generation approaches used in DOE's HIPPS program. Phase 1 of the project is a technical and economic evaluation of the system at the DeRidder site. A Continuation Application will be submitted at the conclusion of Phase 1 for authorization to proceed to testing and design in Phase 2. Phase 2 includes pilot-scale verification of selected system components and preparation of a detailed engineering design and cost estimate for retrofit of the advanced power system at the DeRidder mill. Phase 3 will complete procurement and construction of the system at the DeRidder site along with all required permitting activities. Phase 4 of the project will included plant commissioning, startup and demonstration operations. Design information for the Gasification Island was completed during the quarter. Two vendor quotations were received for the bark/hog fuel dryers. A final layout plan for the major equipment was developed and submitted to DeRidder for review and approval. The Institute of Paper Science and Technology (IPST) completed a subcontract for a laboratory study on VOC emissions from wood waste drying using bark from the DeRidder mill. Samples of DeRidder's lime mud and green liquor dregs were collected and analyzed in GTI's laboratory. It was determined that lime mud is far too fine to be utilized as inert bed material in the

  9. Materials and Area of Study for Advanced Placement Program in American History.

    ERIC Educational Resources Information Center

    Santos, Peter A.

    This paper describes and evaluates benefits of advanced placement programs and identifies materials which can help high school history classroom teachers develop effective advanced placement programs. An advanced placement program is defined as a program which requires a student to do extensive research and writing throughout the school year.…

  10. Solid state nuclear magnetic resonance investigations of advanced energy materials

    NASA Astrophysics Data System (ADS)

    Bennett, George D.

    In order to better understand the physical electrochemical changes that take place in lithium ion batteries and asymmetric hybrid supercapacitors solid state nuclear magnetic resonance (NMR) spectroscopy has been useful to probe and identify changes on the atomic and molecular level. NMR is used to characterize the local environment and investigate the dynamical properties of materials used in electrochemical storage devices (ESD). NMR investigations was used to better understand the chemical composition of the solid electrolyte interphase which form on the negative and positive electrodes of lithium batteries as well as identify the breakdown products that occur in the operation of the asymmetric hybrid supercapacitors. The use of nano-structured particles in the development of new materials causes changes in the electrical, structural and other material properties. NMR was used to investigate the affects of fluorinated and non fluorinated single wall nanotubes (SWNT). In this thesis three experiments were performed using solid state NMR samples to better characterize them. The electrochemical reactions of a lithium ion battery determine its operational profile. Numerous means have been employed to enhance battery cycle life and operating temperature range. One primary means is the choice and makeup of the electrolyte. This study focuses on the characteristics of the solid electrolyte interphase (SEI) that is formed on the electrodes surface during the charge discharge cycle. The electrolyte in this study was altered with several additives in order to determine the influence of the additives on SEI formation as well as the intercalation and de-intercalation of lithium ions in the electrodes. 7Li NMR studies where used to characterize the SEI and its composition. Solid state NMR studies of the carbon enriched acetonitrile electrolyte in a nonaqueous asymmetric hybrid supercapacitor were performed. Magic angle spinning (MAS) coupled with cross polarization NMR

  11. FY2011 Advanced Power Electronics and Electric Motors Annual Progress Report

    SciTech Connect

    Rogers, Susan A.

    2012-01-31

    The Advanced Power Electronics and Electric Motors (APEEM) program within the DOE Vehicle Technologies Program (VTP) provides support and guidance for many cutting-edge automotive technologies now under development. Research is focused on developing revolutionary new power electronics (PE), electric motor (EM), thermal management, and traction drive system technologies that will leapfrog current on-the-road technologies. The research and development (R&D) is also aimed at achieving a greater understanding of and improvements in the way the various new components of tomorrow’s automobiles will function as a unified system to improve fuel efficiency.

  12. FY2012 Advanced Power Electronics and Electric Motors Annual Progress Report

    SciTech Connect

    Rogers, Susan A.

    2013-03-01

    The Advanced Power Electronics and Electric Motors (APEEM) program within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies now under development. Research is focused on developing revolutionary new power electronics (PE), electric motor (EM), thermal management, and traction drive system technologies that will leapfrog current on-the-road technologies. The research and development is also aimed at achieving a greater understanding of and improvements in the way the various new components of tomorrow's automobiles will function as a unified system to improve fuel efficiency.

  13. FY2010 Annual Progress Report for Advanced Power Electronics and Electric Motors

    SciTech Connect

    Rogers, Susan A.

    2011-01-01

    The Advanced Power Electronics and Electric Machines (APEEM) subprogram within the Vehicle Technologies Program provides support and guidance for many cutting-edge automotive technologies now under development. Research is focused on developing revolutionary new power electronics (PE) and electric motor technologies that will leapfrog current on-the-road technologies. The research and development (R&D) is also aimed at achieving a greater understanding of and improvements in the way the various new components of tomorrow’s automobiles will function as a unified system to improve fuel efficiency.

  14. Green energy storage materials: advanced nanostructured materials for lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Tripathi, Alok Mani; Chandrasekar, M. S.; Mitra, Sagar

    2011-06-01

    The projected doubling of world energy consumption in the next fifty years requires certain measures to meet this demand. The ideal energy provider is reliable, efficient, with low emissions source - wind, solar, etc. The low carbon footprint of renewables is an added benefit, which makes them especially attractive during this era of environmental consciousness. Unfortunately, the intermittent nature of energy from these renewables is not suitable for the commercial and residential grid application, unless the power delivery is 24/7, with minimum fluctuation. This requires intervention of efficient electrical energy storage technology to make power generation from renewable practical. The progress to higher energy and power density especially for battery technology will push material to the edge of stability and yet these materials must be rendered safe, stable and with reliable operation throughout their long life. A major challenge for chemical energy storage is developing the ability to store more energy while maintaining stable electrode-electrolyte interface. A structural transformation occurs during charge-discharge cycle, accompanied by a volume change, degrading the microstructure over-time. The need to mitigate this volume and structural change accompanying charge-discharge cycle necessitates going to nanostructured and multifunctional materials that have the potential of dramatically enhancing the energy density and power density.

  15. A test and instrumentation system for the investigation of degradation of electrical insulating materials

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The basic test methods of aging and deterioration mechanisms of electrical insulating materials are discussed. A comprehensive test system developed to study the degradation process is described. This system is completely checked, and calibrated with a few insulating material samples.

  16. The Materials Data Facility: Data Services to Advance Materials Science Research

    NASA Astrophysics Data System (ADS)

    Blaiszik, B.; Chard, K.; Pruyne, J.; Ananthakrishnan, R.; Tuecke, S.; Foster, I.

    2016-07-01

    With increasingly strict data management requirements from funding agencies and institutions, expanding focus on the challenges of research replicability, and growing data sizes and heterogeneity, new data needs are emerging in the materials community. The materials data facility (MDF) operates two cloud-hosted services, data publication and data discovery, with features to promote open data sharing, self-service data publication and curation, and encourage data reuse, layered with powerful data discovery tools. The data publication service simplifies the process of copying data to a secure storage location, assigning data a citable persistent identifier, and recording custom (e.g., material, technique, or instrument specific) and automatically-extracted metadata in a registry while the data discovery service will provide advanced search capabilities (e.g., faceting, free text range querying, and full text search) against the registered data and metadata. The MDF services empower individual researchers, research projects, and institutions to (I) publish research datasets, regardless of size, from local storage, institutional data stores, or cloud storage, without involvement of third-party publishers; (II) build, share, and enforce extensible domain-specific custom metadata schemas; (III) interact with published data and metadata via representational state transfer (REST) application program interfaces (APIs) to facilitate automation, analysis, and feedback; and (IV) access a data discovery model that allows researchers to search, interrogate, and eventually build on existing published data. We describe MDF's design, current status, and future plans.

  17. Performance analysis of co-firing waste materials in an advanced pressurized fluidized-bed combustor

    SciTech Connect

    Bonk, D.L.; McDaniel, H.M.; DeLallo, M.R. Jr.; Zaharchuk, R.

    1995-07-01

    The co-firing of waste materials with coal in utility scale power plants has emerged as an effective approach to produce energy and manage municipal wastes. Leading this approach is the atmospheric fluidized-bed combustor (AFBC). It has demonstrated its commercial acceptance in the utility market as a reliable source of power by burning a variety of waste and alternative fuels. The application of pressurized fluidized-bed combustor (PFBC) technology, although relatively new, can provide significant enhancements to the efficient production of electricity while maintaining the waste management benefits of AFBC. A study was undertaken to investigate the technical and economical feasibility of co-firing a PFBC with coal and municipal and industrial wastes. Focus was placed on the production of electricity and the efficient disposal of wastes for application in central power station and distributed locations. Issues concerning waste material preparation and feed, PFBC operation, plant emissions, and regulations are addressed. The results and conclusions developed are generally applicable to current and advanced PFBC design concepts. Wastes considered for co-firing include municipal solid waste (MSW), sewage sludge, and industrial de-inking sludge. Conceptual designs of two power plants rated at 250 MWe and 150 MWe were developed. Heat and material balances were completed for each plant along with environmental issues. With the PFBC`s operation at high temperature and pressure, efforts were centered on defining feeding systems capable of operating at these conditions. Air emissions and solid wastes were characterized to assess the environmental performance comparing them to state and Federal regulations. This paper describes the results of this investigation, presents conclusions on the key issues, and provides recommendations for further evaluation.

  18. Analysis of the influence of advanced materials for aerospace products R&D and manufacturing cost

    NASA Astrophysics Data System (ADS)

    Shen, A. W.; Guo, J. L.; Wang, Z. J.

    2015-12-01

    In this paper, we pointed out the deficiency of traditional cost estimation model about aerospace products Research & Development (R&D) and manufacturing based on analyzing the widely use of advanced materials in aviation products. Then we put up with the estimating formulas of cost factor, which representing the influences of advanced materials on the labor cost rate and manufacturing materials cost rate. The values ranges of the common advanced materials such as composite materials, titanium alloy are present in the labor and materials two aspects. Finally, we estimate the R&D and manufacturing cost of F/A-18, F/A- 22, B-1B and B-2 aircraft based on the common DAPCA IV model and the modified model proposed by this paper. The calculation results show that the calculation precision improved greatly by the proposed method which considering advanced materials. So we can know the proposed method is scientific and reasonable.

  19. Electrical Load and Energy Management. Course Outline and Instructional Materials.

    ERIC Educational Resources Information Center

    Wang, Paul

    Presented are 13 lecture outlines with accompanying handouts and reference lists for teaching school administrators and maintenance personnel the use of electrical load management as an energy conservation tool. To aid course participants in making cost effective use of electrical power, methods of load management in a variety of situations are…

  20. Advanced Launch System (ALS): Electrical actuation and power systems improve operability and cost picture

    NASA Technical Reports Server (NTRS)

    Sundberg, Gale R.

    1990-01-01

    To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrical power system and controls for all actuation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a specific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military and civilian aircraft, lunar/Martian vehicles, and a multitude of commercial applications.

  1. Advanced Launch System (ALS): Electrical actuation and power systems improve operability and cost picture

    NASA Astrophysics Data System (ADS)

    Sundberg, Gale R.

    To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrical power system and controls for all actuation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a specific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military and civilian aircraft, lunar/Martian vehicles, and a multitude of commercial applications.

  2. Cost/benefit analysis of advanced materials technologies for future aircraft turbine engines

    NASA Technical Reports Server (NTRS)

    Bisset, J. W.

    1976-01-01

    The cost/benefits of advance commercial gas turbine materials are described. Development costs, estimated payoffs and probabilities of success are discussed. The materials technologies investigated are: (1) single crystal turbine blades, (2) high strength hot isostatic pressed turbine disk, (3) advanced oxide dispersion strengthened burner liner, (4) bore entry cooled hot isostatic pressed turbine disk, (5) turbine blade tip - outer airseal system, and (6) advance turbine blade alloys.

  3. Validation of an Advanced Material Model for Simulating the Impact and Shock Response of Composite Materials

    NASA Astrophysics Data System (ADS)

    Clegg, Richard A.; Hayhurst, Colin J.; Nahme, Hartwig

    2001-06-01

    Validation of an advanced continuum based numerical model for the simulation of the shock response of composite materials during high rate transient dynamic loading is described. The constitutive model, implemented in AUTODYN-2D and 3D, allows for the representation of non-linear shock effects in combination with orthotropic stiffness and damage. Simulations of uniaxial flyer plate experiments on aramid and polyethylene fibre composite systems are presented and compared with experiment. The continuum model is shown to reproduce well the experimental VISAR velocity traces at the rear surface of the targets. Finally, practical application of the model as implemented in AUTODYN is demonstrated through the simulation of ballistic and hypervelocity impact events. Comparison with experiment is given where possible.

  4. Advanced electric propulsion system concept for electric vehicles. Addendum 1: Voltage considerations

    NASA Technical Reports Server (NTRS)

    Raynard, A. E.; Forbes, F. E.

    1980-01-01

    The two electric vehicle propulsion systems that best met cost and performance goals were examined to assess the effect of battery pack voltage on system performance and cost. A voltage range of 54 to 540 V was considered for a typical battery pack capacity of 24 k W-hr. The highest battery specific energy (W-hr/kg) and the lowest cost ($/kW-hr) were obtained at the minimum voltage level. The flywheel system traction motor is a dc, mechanically commutated with shunt field control, and due to the flywheel the traction motor and the battery are not subject to extreme peaks of power demand. The basic system uses a permanent-magnet motor with electronic commutation supplied by an ac power control unit. In both systems battery cost were the major factor in system voltage selection, and a battery pack with the minimum voltage of 54 V produced the lowest life-cycle cost. The minimum life-cycle cost for the basic system with lead-acid batteries was $0.057/km and for the flywheel system was $0.037/km.

  5. Prediction of Corrosion of Advanced Materials and Fabricated Components

    SciTech Connect

    A. Anderko; G. Engelhardt; M.M. Lencka; M.A. Jakab; G. Tormoen; N. Sridhar

    2007-09-29

    The goal of this project is to provide materials engineers, chemical engineers and plant operators with a software tool that will enable them to predict localized corrosion of process equipment including fabricated components as well as base alloys. For design and revamp purposes, the software predicts the occurrence of localized corrosion as a function of environment chemistry and assists the user in selecting the optimum alloy for a given environment. For the operation of existing plants, the software enables the users to predict the remaining life of equipment and help in scheduling maintenance activities. This project combined fundamental understanding of mechanisms of corrosion with focused experimental results to predict the corrosion of advanced, base or fabricated, alloys in real-world environments encountered in the chemical industry. At the heart of this approach is the development of models that predict the fundamental parameters that control the occurrence of localized corrosion as a function of environmental conditions and alloy composition. The fundamental parameters that dictate the occurrence of localized corrosion are the corrosion and repassivation potentials. The program team, OLI Systems and Southwest Research Institute, has developed theoretical models for these parameters. These theoretical models have been applied to predict the occurrence of localized corrosion of base materials and heat-treated components in a variety of environments containing aggressive and non-aggressive species. As a result of this project, a comprehensive model has been established and extensively verified for predicting the occurrence of localized corrosion as a function of environment chemistry and temperature by calculating the corrosion and repassivation potentials.To support and calibrate the model, an experimental database has been developed to elucidate (1) the effects of various inhibiting species as well as aggressive species on localized corrosion of nickel

  6. Advanced electric heat pump dual-stroke compressor and system development

    NASA Astrophysics Data System (ADS)

    Veyo, S. E.; Fagan, T. J.

    1983-12-01

    The development of an advanced electric heat pump is discussed. A two-capacity, residential, advanced electric heat pump utilizing a unique dual-stroke compressor was developed. Two nearly identical preprototype split systems of nominally 3.5 tons maximum cooling capacity were designed, built and laboratory tested. The estimated annual energy efficiency of this advanced system is 20 percent better than a two-speed electric heat pump available at contract inception in 1979. This superior performance is due to the synergism of a high-efficiency, dual-stroke reciprocating compressor, a dual-strength high-efficiency single-speed single-phase hermetic drive motor, a single-width, single-entry high-efficiency indoor blower with backward curved cambered plate blades, a high-efficiency multivane axial flow outdoor fan, high-efficiency two-speed air mover motors and a microprocessor control system. The relative proportions of heat exchangers, air flows and compressor size as well as the ratio between high and low capacity were optimized so as to minimize the annual cost of ownership in a northern climate. Constraints placed upon the optimization and design process to ensure comfort provide heating air with a temperature of at least 90(0)F and provide cooling with a sensible-to-total capacity ratio of not more than 0.7. System performance was measured in the laboratory in accordance with applicable codes and procedures. Performance data plus hardware details are provided.

  7. Thermoelectric materials by using two-dimensional materials with negative correlation between electrical and thermal conductivity.

    PubMed

    Lee, Myoung-Jae; Ahn, Ji-Hoon; Sung, Ji Ho; Heo, Hoseok; Jeon, Seong Gi; Lee, Woo; Song, Jae Yong; Hong, Ki-Ha; Choi, Byeongdae; Lee, Sung-Hoon; Jo, Moon-Ho

    2016-01-01

    In general, in thermoelectric materials the electrical conductivity σ and thermal conductivity κ are related and thus cannot be controlled independently. Previously, to maximize the thermoelectric figure of merit in state-of-the-art materials, differences in relative scaling between σ and κ as dimensions are reduced to approach the nanoscale were utilized. Here we present an approach to thermoelectric materials using tin disulfide, SnS2, nanosheets that demonstrated a negative correlation between σ and κ. In other words, as the thickness of SnS2 decreased, σ increased whereas κ decreased. This approach leads to a thermoelectric figure of merit increase to 0.13 at 300 K, a factor ∼1,000 times greater than previously reported bulk single-crystal SnS2. The Seebeck coefficient obtained for our two-dimensional SnS2 nanosheets was 34.7 mV K(-1) for 16-nm-thick samples at 300 K. PMID:27323662

  8. Thermoelectric materials by using two-dimensional materials with negative correlation between electrical and thermal conductivity

    PubMed Central

    Lee, Myoung-Jae; Ahn, Ji-Hoon; Sung, Ji Ho; Heo, Hoseok; Jeon, Seong Gi; Lee, Woo; Song, Jae Yong; Hong, Ki-Ha; Choi, Byeongdae; Lee, Sung-Hoon; Jo, Moon-Ho

    2016-01-01

    In general, in thermoelectric materials the electrical conductivity σ and thermal conductivity κ are related and thus cannot be controlled independently. Previously, to maximize the thermoelectric figure of merit in state-of-the-art materials, differences in relative scaling between σ and κ as dimensions are reduced to approach the nanoscale were utilized. Here we present an approach to thermoelectric materials using tin disulfide, SnS2, nanosheets that demonstrated a negative correlation between σ and κ. In other words, as the thickness of SnS2 decreased, σ increased whereas κ decreased. This approach leads to a thermoelectric figure of merit increase to 0.13 at 300 K, a factor ∼1,000 times greater than previously reported bulk single-crystal SnS2. The Seebeck coefficient obtained for our two-dimensional SnS2 nanosheets was 34.7 mV K−1 for 16-nm-thick samples at 300 K. PMID:27323662

  9. Advanced characterization of hysteretic materials by object-oriented software

    NASA Astrophysics Data System (ADS)

    Ionita, V.; Gavrila, H.

    2002-04-01

    A new object-oriented software, which is dedicated for the characterization of magnetic materials, including the hysteresis effect, is presented. The product allows the development and utilization of an information base, containing experimental and numerical data related to the magnetic material behaviour. The materials may be modelled with different hysteresis models (Preisach, Jiles-Atherton, etc.).

  10. An advanced energy management system for controlling the ultracapacitor discharge and improving the electric vehicle range

    NASA Astrophysics Data System (ADS)

    Armenta, Jesús; Núñez, Ciro; Visairo, Nancy; Lázaro, Isabel

    2015-06-01

    Over the last years issues regarding both the use and the improvement of energy management in electric vehicles have been highlighted by industry and academic fields. Some of the research has been focused on exploiting the ultracapacitor characteristics and on protecting the battery life. From this standpoint, this paper proposes an advanced energy management system based on the adequate discharge of the ultracapacitor bank in order to utilize all the energy available from the regenerative breaking. In this way, the energy consumption is reduced and the electric vehicle range is increased. This strategy, based on simple rules, takes advantage of the high power density of the ultracapacitor and prevents an overstress of the battery. The benefits are featured using three standard drive cycles for a 1550 kg electric vehicle via simulations.

  11. Advanced electric vehicle controls and power conversion electronics for transit buses and light rail

    SciTech Connect

    Peticolas, B.W.

    1994-12-31

    The majority of development which has taken place in AC electric vehicle drive technology has focused on small vehicles (i.e. 3,000 lbs and less) with emphasis on high performance and rapid acceleration. Examples of this type of development are the GM Impact and the Ford Ecostar. These vehicles have been developed to demonstrate technology advances by Detroit, but the high performance capabilities of these vehicles have raised expectations that cannot be met with contemporary batteries, or perhaps, any batteries. Larger vehicles such as buses, trucks, and even light rail cars may in fact be better near term targets for electric conversion since many of these vehicles have lower performance demands, and operate on fixed routes with designated stops for several minutes, allowing ``opportunity`` charging for range extension. The basis of this paper is to propose a near term drive system for large vehicles that overcomes some of the problems of electric vehicles to date, while providing a platform which is adaptable to future improvements in technology. The advanced transit bus will not only require power electronics for the vehicle drive, but will require power electronics and electric actuators for a variety of nonpropulsion equipment such as air conditioning, wheel chair lifts, and power steering. 6 refs.

  12. Advances in Materials Science for Environmental and Energy Technologies II

    SciTech Connect

    Matyas, Dr Josef; Ohji, Tatsuki; Liu, Xingbo; Paranthaman, Mariappan Parans; Devanathan, Ram; Fox, Kevin; Singh, Mrityunjay; Wong-ng, Winnie

    2013-01-01

    The Materials Science and Technology 2012 Conference and Exhibition (MS&T'12) was held October 7-11, 2012, in Pittsburgh, Pennsylvania. One of the major themes of the conference was Environmental and Energy Issues. Papers from five of the symposia held under that theme are invluded in this volume. These symposia included Materials Issues in Nuclear Waste Management for the 21st Century; Green Technologies for Materials Manufacturing and Processing IV; Energy Storage: Materials, Systems and Applications; Energy Conversion-Photovoltaic, Concentraing Solar Power and Thermoelectric; and Materials Development for Nuclear Applications and Extreme Environments.

  13. Solid State Ionics Advanced Materials for Emerging Technologies

    NASA Astrophysics Data System (ADS)

    Chowdari, B. V. R.; Careem, M. A.; Dissanayake, M. A. K. L.; Rajapakse, R. M. G.; Seneviratne, V. A.

    2006-06-01

    . Invited papers. Cathodic properties of Al-doped LiCoO[symbol] prepared by molten salt method Li-Ion batteries / M. V. Reddy, G. V. Subba Rao, B. V. R. Chowdari. Layered ion-electron conducting materials / M. A. Santa Ana, E. Benavente, G. González. LiNi[symbol]Co[symbol]O[symbol] cathode thin-film prepared by RF sputtering for all-solid-state rechargeable microbatteries / X. J. Zhu ... [et al.] -- Contributed papers. Contributed papers. Nanocomposite cathode for SOFCs prepared by electrostatic spray deposition / A. Princivalle, E. Djurado. Effect of the addition of nanoporous carbon black on the cycling characteristics of Li[symbol]Co[symbol](MoO[symbol])[symbol] for lithium batteries / K. M. Begam, S. R. S. Prabaharan. Protonic conduction in TiP[symbol]O[symbol] / V. Nalini, T. Norby, A. M. Anuradha. Preparation and electrochemical LiMn[symbol]O[symbol] thin film by a solution deposition method / X. Y. Gan ... [et al.]. Synthesis and characterization LiMPO[symbol] (M = Ni, Co) / T. Savitha, S. Selvasekarapandian, C. S. Ramya. Synthesis and electrical characterization of LiCoO[symbol] LiFeO[symbol] and NiO compositions / A. Wijayasinghe, B. Bergman. Natural Sri Lanka graphite as conducting enhancer in manganese dioxide (Emd type) cathode of alkaline batteries / N. W. B. Balasooriya ... [et al.]. Electrochemical properties of LiNi[symbol]Al[symbol]Zn[symbol]O[symbol] cathode material synthesized by emulsion method / B.-H. Kim ... [et al.]. LiNi[symbol]Co[symbol]O[symbol] cathode materials synthesized by particulate sol-gel method for lithium ion batteries / X. J. Zhu ... [et al.]. Pulsed laser deposition of highly oriented LiCoO[symbol] and LiMn[symbol]O[symbol] thin films for microbattery applications / O. M. Hussain ... [et al.]. Preparation of LiNi[symbol]Co[symbol]O[symbol] thin films by a sol-gel method / X. J. Zhu ... [et al.]. Electrochemical lithium insertion into a manganese dioxide electrode in aqueous solutions / M. Minakshi ... [et al.]. AC impedance

  14. Part A - Advanced turbine systems. Part B - Materials/manufacturing element of the Advanced Turbine Systems Program

    SciTech Connect

    Karnitz, M.A.

    1996-06-01

    The DOE Offices of Fossil Energy and Energy Efficiency and Renewable Energy have initiated a program to develop advanced turbine systems for power generation. The objective of the Advanced Turbine Systems (ATS) Program is to develop ultra-high efficiency, environmentally superior, and cost competitive gas turbine systems for utility and industrial applications. One of the supporting elements of the ATS Program is the Materials/Manufacturing Technologies Task. The objective of this element is to address the critical materials and manufacturing issues for both industrial and utility gas turbines.

  15. Advanced materials and design for low temperature SOFCs

    DOEpatents

    Wachsman, Eric D.; Yoon, Heesung; Lee, Kang Taek; Camaratta, Matthew; Ahn, Jin Soo

    2016-05-17

    Embodiments of the invention are directed to SOFC with a multilayer structure comprising a porous ceramic cathode, optionally a cathodic triple phase boundary layer, a bilayer electrolyte comprising a cerium oxide comprising layer and a bismuth oxide comprising layer, an anion functional layer, and a porous ceramic anode with electrical interconnects, wherein the SOFC displays a very high power density at temperatures below 700.degree. C. with hydrogen or hydrocarbon fuels. The low temperature conversion of chemical energy to electrical energy allows the fabrication of the fuel cells using stainless steel or other metal alloys rather than ceramic conductive oxides as the interconnects.

  16. Carbon and related materials for thermal and electrical applications

    NASA Astrophysics Data System (ADS)

    Aoyagi, Yasuhiro

    High thermal stability has been attained in polyol ester by using a sterically half-hindered phenolic primary antioxidant and a thiopropionate secondary antioxidant. Carbon black and boron nitride (BN) serve as antioxidants in the presence of either primary antioxidant or secondary antioxidant at 200°C. BN paste shows an estimated 100°C lifetime of 19 years, compared to 1.3 years for the carbon black paste and 0.10 year for commercial silver paste. Phase-change materials (PCMs) with high thermal stability and high heat of fusion have been attained by using antioxidants (mainly hydrocarbons with linear segments). Their heat of fusion is much higher than those of commercial PCMs. The use of 98.0 wt.% thiopropionate antioxidant with 2.0 wt.% half-hindered phenolic antioxidant as the matrix and 16 vol.% BN particles gives 100°C lifetime indicator 5.3 years, in contrast to 0.95 year or less for the commercial PCMs. Carbon-based films with thickness 1-13 mum, electrical resistivity 6 x 10-4 - 3 O.cm, and strong bonding to alumina, have been attained through the use of EPON SU 2.5 epoxy and an amine curing agent as the carbon precursor, and a carbonization temperature of 650°C. Nickel nanoparticles (filamentary) are more effective for enhancing the conductivity than silver nanoparticles (not filamentary) at the same volume fraction. Even the combined use of carbon nanotube and silver is less effective than nickel. A three-dimensional microstructure in the form of a microscale bridge on alumina has been attained by using a novel low-cost process that involves thermoplastic spacer (wax) evaporation during pyrolysis of an epoxy-based film that coats the spacer and a part of the substrate. Multiwalled carbon nanotube as a filler is effective for reducing cracking during pyrolysis. A bridge with a girder of length 90-300 microm, separated from the substrate by a height of 5-15 mum, has been attained.

  17. Characterization and development of materials for advanced textile composites

    NASA Technical Reports Server (NTRS)

    Hartness, J. Timothy; Greene, Timothy L.; Taske, Leo E.

    1993-01-01

    Work ongoing under the NASA Langley - Advanced Composite Technology (ACT) program is discussed. The primary emphasis of the work centers around the development and characterization of graphite fiber that has been impregnated with an epoxy powder. Four epoxies have been characterized in towpreg form as to their weaveability and braidability. Initial mechanical properties have been generated on each resin system. These include unidirectional as well as 8-harness satin cloth. Initial 2D and 3D weaving and braiding trials will be reported on as well as initial efforts to develop towpreg suitable for advanced tow placement.

  18. Enabling Renewable Energy and the Future Grid with Advanced Electricity Storage

    SciTech Connect

    Yang, Zhenguo; Liu, Jun; Baskaran, Suresh; Imhoff, Carl H.; Holladay, Jamelyn D.

    2010-08-06

    Environmental concerns about using fossil fuels and their resource constrains, along with that on energy security, have spurred great interests in generating electrical energy from renewable sources such as wind and solar. The variable and stochastic nature of renewable sources however makes solar and wind power difficult to manage, especially at high levels of penetration. To effectively use the intermittent renewable energy and enable its delivery demand electrical energy storage (EES) that can also improve the reliability, stability, and efficiency of the electrical grid, which is expected to support plug-in electrical vehicles; enable real-time, two-way communication to balance demand and supply. While EES has gained wide attention for hybrid and electrical vehicle (e.g. plug-in-hybrid electrical) needs, public awareness and understanding of the critical challenges in energy storage for renewable integration and the future grid is relatively lacking. This paper examines the benefits and challenges of EES, in particular electrochemical storage or battery technologies, and discusses the fundamental principles, economics, and feasibility of the storage technologies. It intends to provide an understanding of the needs and challenges of electrical storage technologies for the stationary applications and offer general directions of research and development to the materials community.

  19. Concentrating solar power (CSP) power cycle improvements through application of advanced materials

    NASA Astrophysics Data System (ADS)

    Siefert, John A.; Libby, Cara; Shingledecker, John

    2016-05-01

    Concentrating solar power (CSP) systems with thermal energy storage (TES) capability offer unique advantages to other renewable energy technologies in that solar radiation can be captured and stored for utilization when the sun is not shining. This makes the technology attractive as a dispatchable resource, and as such the Electric Power Research Institute (EPRI) has been engaged in research and development activities to understand and track the technology, identify key technical challenges, and enable improvements to meet future cost and performance targets to enable greater adoption of this carbon-free energy resource. EPRI is also involved with technically leading a consortium of manufacturers, government labs, and research organizations to enable the next generation of fossil fired power plants with advanced ultrasupercritical (A-USC) steam temperatures up to 760°C (1400°F). Materials are a key enabling technology for both of these seemingly opposed systems. This paper discusses how major strides in structural materials for A-USC fossil fired power plants may be translated into improved CSP systems which meet target requirements.

  20. Advanced Materials for Sodium-Beta Alumina Batteries: Status, Challenges and Perspectives

    SciTech Connect

    Lu, Xiaochuan; Xia, Guanguang; Lemmon, John P.; Yang, Zhenguo

    2010-05-01

    The increasing penetration of renewable energy and the trend toward clean, efficient transportation have spurred growing interests in sodium-beta alumina batteries that store electrical energy via sodium ion transport across a β"-Al2O3 solid electrolyte at elevated temperatures (typically 300~350°C). Currently, the negative electrode or anode is metallic sodium in molten state during battery operation; the positive electrode or cathode can be molten sulfur (Na-S battery) or solid transition metal halides plus a liquid phase secondary electrolyte (e.g., ZEBRA battery). Since the groundbreaking works in the sodium-beta alumina batteries a few decades ago, encouraging progress has been achieved in improving battery performance, along with cost reduction. However there remain issues that hinder broad applications and market penetration of the technologies. To better the Na-beta alumina technologies require further advancement in materials along with component and system design and engineering. This paper offers a comprehensive review on materials of electrodes and electrolytes for the Na-beta alumina batteries and discusses the challenges ahead for further technology improvement.

  1. Advanced materials for sodium-beta alumina batteries: Status, challenges and perspectives

    SciTech Connect

    Lu, XC; Xia, GG; Lemmon, JP; Yang, ZG

    2010-05-01

    The increasing penetration of renewable energy and the trend toward clean, efficient transportation have spurred growing interests in sodium-beta alumina batteries that store electrical energy via sodium ion transport across a beta ''-Al(2)O(3) solid electrolyte at elevated temperatures (typically 300-350 degrees C ). Currently, the negative electrode or anode is metallic sodium in molten state during battery operation; the positive electrode or cathode can be molten sulfur (Na-S battery) or solid transition metal halides plus a liquid phase secondary electrolyte (e.g., ZEBRA battery). Since the groundbreaking works in the sodium-beta alumina batteries a few decades ago, encouraging progress has been achieved in improving battery performance, along with cost reduction. However, there remain issues that hinder broad applications and market penetration of the technologies. To better the Na-beta alumina technologies require further advancement in materials along with component and system design and engineering. This paper offers a comprehensive review on materials of electrodes and electrolytes for the Na-beta alumina batteries and discusses the challenges ahead for further technology improvement. (C) 2009 Published by Elsevier B.V.

  2. Bricklaying Curriculum: Advanced Bricklaying Techniques. Instructional Materials. Revised.

    ERIC Educational Resources Information Center

    Turcotte, Raymond J.; Hendrix, Laborn J.

    This curriculum guide is designed to assist bricklaying instructors in providing performance-based instruction in advanced bricklaying. Included in the first section of the guide are units on customized or architectural masonry units; glass block; sills, lintels, and copings; and control (expansion) joints. The next two units deal with cut,…

  3. Advanced Industrial Materials Program. Annual progress report, FY 1993

    SciTech Connect

    Stooksbury, F.

    1994-06-01

    Mission of the AIM program is to commercialize new/improved materials and materials processing methods that will improve energy efficiency, productivity, and competitiveness. Program investigators in the DOE national laboratories are working with about 100 companies, including 15 partners in CRDAs. Work is being done on intermetallic alloys, ceramic composites, metal composites, polymers, engineered porous materials, and surface modification. The program supports other efforts in the Office of Industrial Technologies to assist the energy-consuming process industries. The aim of the AIM program is to bring materials from basic research to industrial application to strengthen the competitive position of US industry and save energy.

  4. Composite magnetostrictive materials for advanced automotive magnetomechanical sensors

    NASA Astrophysics Data System (ADS)

    McCallum, R. W.; Dennis, K. W.; Jiles, D. C.; Snyder, J. E.; Chen, Y. H.

    2001-04-01

    In this paper we present the development of a composite magnetostrictive material for automotive applications. The material is based on cobalt ferrite, CoOṡFe2O3, and contains a small fraction of metallic matrix phase that serves both as a liquid-phase sintering aid during processing and enhances the mechanical properties over those of a simple sintered ferrite ceramic. In addition the metal matrix makes it possible to braze the material, making the assembly of a sensor relatively simple. The material exhibits good sensitivity and should have high corrosion resistance, while at the same time it is low in cost.

  5. Creep and fatigue research efforts on advanced materials

    NASA Technical Reports Server (NTRS)

    Gayda, John

    1987-01-01

    Two of the more important materials problems encountered in turbine blades of aircraft engines are creep and fatigue. To withstand these high-temperature phenomena modern engines utilize single-crystal, nickel-based superalloys as the material of choice in critical applications. Recent research activities at Lewis on single-crystal blading material as well as future research initiatives on metal matrix composites related to creep and fatigue are discussed. The goal of these research efforts is improving the understanding of microstructure-property relationships and thereby guide material development.

  6. Creep and fatigue research efforts on advanced materials

    NASA Technical Reports Server (NTRS)

    Gayda, John

    1990-01-01

    Two of the more important materials problems encountered in turbine blades of aircraft engines are creep and fatigue. To withstand these high-temperature phenomena, modern engines utilize single-crystal, nickel-base superalloys as the material of choice in critical applications. This paper will present recent research activities at NASA's Lewis Research Center on single-crystal blading material, related to creep and fatique. The goal of these research efforts is to improve the understanding of microstructure-property relationships and thereby guide material development.

  7. Effect of electric pulse processing on physical and chemical properties of inorganic materials

    NASA Astrophysics Data System (ADS)

    Sakipova, S. E.; Nussupbekov, B. R.; Ospanova, D.; Khassenov, A.; Sakipova, Sh E.

    2015-04-01

    This article analyzes various aspects of the practical application of electric pulse technology of industrial raw materials processing as a result of a spark electric discharge in a liquid solution of the raw material under processing. The object of the study are samples of technogenic materials from a deposit in Central Kazakhstan, which are crushed and ground to particles with a preset degree of fragmentation. The electric pulse processing is performed by using different numbers of discharges. The effect of electric pulse processing with different electrical parameters is carried out on the basis of comparison of the properties and structure of metal-containing and industrial raw materials after machining and electric pulse processing. The X-ray spectral microanalysis was performed using a scanning microscope. The researchers obtained data on changes in the microstructure and elemental composition of inorganic material samples as a result of electric pulse processing. It was established that the technology of electric pulse crushing and grinding of inorganic materials makes it possible to obtain not only a final product with desired size of dispersed particles, but also to change their physical and chemical properties.

  8. Near net shape processing: A necessity for advanced materials applications

    NASA Technical Reports Server (NTRS)

    Kuhn, Howard A.

    1993-01-01

    High quality discrete parts are the backbones for successful operation of equipment used in transportation, communication, construction, manufacturing, and appliances. Traditional shapemaking for discrete parts is carried out predominantly by machining, or removing unwanted material to produce the desired shape. As the cost and complexity of modern materials escalates, coupled with the expense and environmental hazards associated with handling of scrap, it is increasingly important to develop near net shape processes for these materials. Such processes involve casting of liquid materials, consolidation of powder materials, or deformation processing of simple solid shapes into the desired shape. Frequently, several of these operations may be used in sequence to produce a finished part. The processes for near net shape forming may be applied to any type of material, including metals, polymers, ceramics, and their composites. The ability to produce shapes is the key to implementation of laboratory developments in materials science into real world applications. This seminar presents an overview of near net shapemaking processes, some application examples, current developments, and future research opportunities.

  9. DOE FreedomCAR and vehicle technologies program advanced power electronic and electrical machines annual review report

    SciTech Connect

    Olszewski, Mitch

    2006-10-11

    This report is a summary of the Review Panel at the FY06 DOE FreedomCAR and Vehicle Technologies (FCVT) Annual Review of Advanced Power Electronics and Electric Machine (APEEM) research activities held on August 15-17, 2006.

  10. 10 CFR 37.77 - Advance notification of shipment of category 1 quantities of radioactive material.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... of radioactive material. 37.77 Section 37.77 Energy NUCLEAR REGULATORY COMMISSION PHYSICAL PROTECTION OF CATEGORY 1 AND CATEGORY 2 QUANTITIES OF RADIOACTIVE MATERIAL Physical Protection in Transit § 37.77 Advance notification of shipment of category 1 quantities of radioactive material. As specified...

  11. Recent advances in 2D materials for photocatalysis

    NASA Astrophysics Data System (ADS)

    Luo, Bin; Liu, Gang; Wang, Lianzhou

    2016-03-01

    Two-dimensional (2D) materials have attracted increasing attention for photocatalytic applications because of their unique thickness dependent physical and chemical properties. This review gives a brief overview of the recent developments concerning the chemical synthesis and structural design of 2D materials at the nanoscale and their applications in photocatalytic areas. In particular, recent progress on the emerging strategies for tailoring 2D material-based photocatalysts to improve their photo-activity including elemental doping, heterostructure design and functional architecture assembly is discussed.

  12. Advanced composites: Fabrication processes for selected resin matrix materials

    NASA Technical Reports Server (NTRS)

    Welhart, E. K.

    1976-01-01

    This design note is based on present state of the art for epoxy and polyimide matrix composite fabrication technology. Boron/epoxy and polyimide and graphite/epoxy and polyimide structural parts can be successfully fabricated. Fabrication cycles for polyimide matrix composites have been shortened to near epoxy cycle times. Nondestructive testing has proven useful in detecting defects and anomalies in composite structure elements. Fabrication methods and tooling materials are discussed along with the advantages and disadvantages of different tooling materials. Types of honeycomb core, material costs and fabrication methods are shown in table form for comparison. Fabrication limits based on tooling size, pressure capabilities and various machining operations are also discussed.

  13. Recent Advances in Materials for All-Ceramic Restorations

    PubMed Central

    Griggs, Jason A.

    2010-01-01

    SYNOPSIS The past three years of research on materials for all-ceramic veneers, inlays, onlays, single-unit crowns, and multi-unit restorations are reviewed. The primary changes in the field were the proliferation of zirconia-based frameworks and computer-aided fabrication of prostheses, as well as, a trend toward more clinically relevant in vitro test methods. This report includes an overview of ceramic fabrication methods, suggestions for critical assessment of material property data, and a summary of clinical longevity for prostheses constructed of various materials. PMID:17586152

  14. Advanced Modeling and Materials in Kraft Pulp Mills

    SciTech Connect

    Keiser, J.R.; Gorog, J.P.

    2002-05-15

    This CRADA provided technical support to the Weyerhaeuser Company on a number of issues related to the performance and/or selection of materials at a number of locations in a pulp and paper mill. The studies related primarily to components for black liquor recovery boilers, but some effort was directed toward black liquor gasifiers and rolls for paper machines. The purpose of this CRADA was to assist Weyerhaeuser in the evaluation of materials exposed in various paper mill environments and to provide direction in the selection of alternate materials, when appropriate.

  15. Progress in advanced high temperature turbine materials, coatings, and technology

    NASA Technical Reports Server (NTRS)

    Freche, J. C.; Ault, G. M.

    1977-01-01

    Material categories as well as coatings and recent turbine cooling developments are reviewed. Current state of the art is identified, and as assessment, when appropriate, of progress, problems, and future directions is provided.

  16. Inspection of composite materials with an advanced ultrasonic flaw detector

    NASA Astrophysics Data System (ADS)

    Yamamoto, W.

    The structures and shapes of the composite material products are described. Methods of ultrasonic wave detection are described. New damage detection equipment for laminate and honeycomb structures is addressed.

  17. Thermal interface materials: advancements for "beating the heat" in microelectronics.

    SciTech Connect

    Galloway, Jeffrey A.; Rae, David F.; Rightley, Michael J.; Emerson, John Allen

    2005-05-01

    As electronic assemblies become more compact and with increased processing bandwidth, the escalating thermal energy has become more difficult to manage. The major limitation has been nonmetallic joining using poor thermal interface materials.

  18. Development of Processing Techniques for Advanced Thermal Protection Materials

    NASA Technical Reports Server (NTRS)

    Selvaduray, Guna; Lacson, Jamie; Collazo, Julian

    1997-01-01

    During the period June 1, 1996 through May 31, 1997, the main effort has been in the development of materials for high temperature applications. Thermal Protection Systems (TPS) are constantly being tested and evaluated for thermal shock resistance, high temperature dimensional stability, and tolerance to environmental effects. Materials development was carried out by using many different instruments and methods, ranging from intensive elemental analysis to testing the physical attributes of a material. The material development concentrated on two key areas: (1) development of coatings for carbon/carbon composites, and (2) development of ultra-high temperature ceramics (UHTC). This report describes the progress made in these two areas of research during this contract period.

  19. Advances in monoliths and related porous materials for microfluidics.

    PubMed

    Knob, Radim; Sahore, Vishal; Sonker, Mukul; Woolley, Adam T

    2016-05-01

    In recent years, the use of monolithic porous polymers has seen significant growth. These materials present a highly useful support for various analytical and biochemical applications. Since their introduction, various approaches have been introduced to produce monoliths in a broad range of materials. Simple preparation has enabled their easy implementation in microchannels, extending the range of applications where microfluidics can be successfully utilized. This review summarizes progress regarding monoliths and related porous materials in the field of microfluidics between 2010 and 2015. Recent developments in monolith preparation, solid-phase extraction, separations, and catalysis are critically discussed. Finally, a brief overview of the use of these porous materials for analysis of subcellular and larger structures is given. PMID:27190564

  20. Advance assessment for movement of Haz Cat 3 radioactive materials.

    SciTech Connect

    Vosburg, Susan K.

    2010-04-01

    The current packaging of most HC-3 radioactive materials at SNL/NM do not meet DOT requirements for offsite shipment. SNL/NM is transporting HC-3 quantities of radioactive materials from their storage locations in the Manzano Nuclear Facilities bunkers to facilities in TA-5 to be repackaged for offsite shipment. All transportation of HC-3 rad material by SNL/NM is onsite (performed within the confines of KAFB). Transport is performed only by the Regulated Waste/Nuclear Material Disposition Department. Part of the HC3T process is to provide the CAT with the following information at least three days prior to the move: (1) RFt-Request for transfer; (2) HC3T movement report; (3) Radiological survey; and (4) Transportation Route Map.

  1. Incorporation of metal related materials into electrically neutral polymers

    NASA Technical Reports Server (NTRS)

    St. Clair, A. K.; Taylor, L. T.

    1981-01-01

    Developments in the field of metal-containing polymers are reviewed with emphasis on neutral polymers incorporating dissolved metal salts, metal complexes, organometallic compounds, and metals. Polymer systems discussed include: polyamides, polyimides, polyalcohols, polyesters, polyacetylene, polyethylene, and polysiloxane. Most of the studies focus on the modification of polymer properties such as adhesive properties, thermal behavior, electrical conductivity, polymer flammability, and mechanical properties.

  2. Recent Advances in Pulp Capping Materials: An Overview

    PubMed Central

    Qureshi, Asma; E., Soujanya; Nandakumar; Pratapkumar; Sambashivarao

    2014-01-01

    Emphasis has shifted from the “doomed” organ concept of an exposed pulp to one of hope and recovery. The era of vital-pulp therapy has been greatly enhanced with the introduction of various pulp capping materials. The aim of this article is to summarize and discuss about the various and newer pulp capping materials used for protection of the dentin-pulp complex. PMID:24596805

  3. Advanced and In Situ Analytical Methods for Solar Fuel Materials.

    PubMed

    Chan, Candace K; Tüysüz, Harun; Braun, Artur; Ranjan, Chinmoy; La Mantia, Fabio; Miller, Benjamin K; Zhang, Liuxian; Crozier, Peter A; Haber, Joel A; Gregoire, John M; Park, Hyun S; Batchellor, Adam S; Trotochaud, Lena; Boettcher, Shannon W

    2016-01-01

    In situ and operando techniques can play important roles in the development of better performing photoelectrodes, photocatalysts, and electrocatalysts by helping to elucidate crucial intermediates and mechanistic steps. The development of high throughput screening methods has also accelerated the evaluation of relevant photoelectrochemical and electrochemical properties for new solar fuel materials. In this chapter, several in situ and high throughput characterization tools are discussed in detail along with their impact on our understanding of solar fuel materials. PMID:26267386

  4. Advances in Suture Material for Obstetric and Gynecologic Surgery

    PubMed Central

    Greenberg, James A; Clark, Rachel M

    2009-01-01

    Despite millennia of experience with wound closure biomaterials, no study or surgeon has yet identified the perfect suture for all situations. Tissue characteristics, tensile strength, reactivity, absorption rates, and handling properties should be taken into account when selecting a wound closure suture. This review discusses the wound healing process and the biomechanical properties of currently available suture materials to better understand how to choose suture material in obstetrics and gynecology. PMID:19826572

  5. Advanced techniques for characterization of ion beam modified materials

    DOE PAGESBeta

    Zhang, Yanwen; Debelle, Aurélien; Boulle, Alexandre; Kluth, Patrick; Tuomisto, Filip

    2014-10-30

    Understanding the mechanisms of damage formation in materials irradiated with energetic ions is essential for the field of ion-beam materials modification and engineering. Utilizing incident ions, electrons, photons, and positrons, various analysis techniques, including Rutherford backscattering spectrometry (RBS), electron RBS, Raman spectroscopy, high-resolution X-ray diffraction, small-angle X-ray scattering, and positron annihilation spectroscopy, are routinely used or gaining increasing attention in characterizing ion beam modified materials. The distinctive information, recent developments, and some perspectives in these techniques are reviewed in this paper. Applications of these techniques are discussed to demonstrate their unique ability for studying ion-solid interactions and the corresponding radiationmore » effects in modified depths ranging from a few nm to a few tens of μm, and to provide information on electronic and atomic structure of the materials, defect configuration and concentration, as well as phase stability, amorphization and recrystallization processes. Finally, such knowledge contributes to our fundamental understanding over a wide range of extreme conditions essential for enhancing material performance and also for design and synthesis of new materials to address a broad variety of future energy applications.« less

  6. Advanced techniques for characterization of ion beam modified materials

    SciTech Connect

    Zhang, Yanwen; Debelle, Aurélien; Boulle, Alexandre; Kluth, Patrick; Tuomisto, Filip

    2014-10-30

    Understanding the mechanisms of damage formation in materials irradiated with energetic ions is essential for the field of ion-beam materials modification and engineering. Utilizing incident ions, electrons, photons, and positrons, various analysis techniques, including Rutherford backscattering spectrometry (RBS), electron RBS, Raman spectroscopy, high-resolution X-ray diffraction, small-angle X-ray scattering, and positron annihilation spectroscopy, are routinely used or gaining increasing attention in characterizing ion beam modified materials. The distinctive information, recent developments, and some perspectives in these techniques are reviewed in this paper. Applications of these techniques are discussed to demonstrate their unique ability for studying ion-solid interactions and the corresponding radiation effects in modified depths ranging from a few nm to a few tens of μm, and to provide information on electronic and atomic structure of the materials, defect configuration and concentration, as well as phase stability, amorphization and recrystallization processes. Finally, such knowledge contributes to our fundamental understanding over a wide range of extreme conditions essential for enhancing material performance and also for design and synthesis of new materials to address a broad variety of future energy applications.

  7. Investigation of the electrical properties of some dental composite restorative materials before and after laser exposure.

    PubMed

    ElKestawy, M A; Saafan, S A; Shehata, M M; Saafan, A M

    2006-10-01

    Some electrical properties, such as piezoelectricity, ac conductivity, dielectric constant and loss tangent of nine commercial types of dental composite restorative materials, have been investigated before and after laser exposure for 3s to study the effect of a probable laser exposure during some surgeries on the electrical properties of these materials. No piezoelectric effect has been found in these materials before and after laser exposure. The materials were found to be good insulators (very poorly conducting materials). The temperature and frequency dependence of ac conductivity, dielectric constant and loss tangent have not shown significant changes in values after laser exposure. PMID:16387356

  8. Carbonaceous materials and their advances as a counter electrode in dye-sensitized solar cells: challenges and prospects.

    PubMed

    Kouhnavard, Mojgan; Ludin, Norasikin Ahmad; Ghaffari, Babak V; Sopian, Kamarozzaman; Ikeda, Shoichiro

    2015-05-11

    Dye-sensitized solar cells (DSSCs) serve as low-costing alternatives to silicon solar cells because of their low material and fabrication costs. Usually, they utilize Pt as the counter electrode (CE) to catalyze the iodine redox couple and to complete the electric circuit. Given that Pt is a rare and expensive metal, various carbon materials have been intensively investigated because of their low costs, high surface areas, excellent electrochemical stabilities, reasonable electrochemical activities, and high corrosion resistances. In this feature article, we provide an overview of recent studies on the electrochemical properties and photovoltaic performances of carbon-based CEs (e.g., activated carbon, nanosized carbon, carbon black, graphene, graphite, carbon nanotubes, and composite carbon). We focus on scientific challenges associated with each material and highlight recent advances achieved in overcoming these obstacles. Finally, we discuss possible future directions for this field of research aimed at obtaining highly efficient DSSCs. PMID:25925421

  9. Preparation, Fabrication, and Evaluation of Advanced Polymeric and Composite Materials

    NASA Technical Reports Server (NTRS)

    Orwoll, Robert A.

    1997-01-01

    The thesis titles are given below: physical and mechanical behavior of amorphous poly(arylene ether-co-imidasole)s and poly(arylene ether-co-imidasole) modification epoxies; the requirements of patentability as applied to the chemical arts; fabrication of thermoplastic polymer composite ribbon; blend of reactive diluents with phenylethynyl-terminated arylene ether oligomers; the synthesis, characterization, and application of ether-containing polyimides; the synthesis of reflective and electrically conductive polyimide films via an in-situ self-metalization procedure using silver (I) complexes; the thermal cure of phenylethynyl terminated polyimides and selected model compounds; and the synthesis, characterization, and molecular modeling of cyclic arylene ether oligomers.

  10. Fabrication of advanced electrochemical energy materials using sol-gel processing techniques

    NASA Technical Reports Server (NTRS)

    Chu, C. T.; Chu, Jay; Zheng, Haixing

    1995-01-01

    Advanced materials play an important role in electrochemical energy devices such as batteries, fuel cells, and electrochemical capacitors. They are being used as both electrodes and electrolytes. Sol-gel processing is a versatile solution technique used in fabrication of ceramic materials with tailored stoichiometry, microstructure, and properties. The application of sol-gel processing in the fabrication of advanced electrochemical energy materials will be presented. The potentials of sol-gel derived materials for electrochemical energy applications will be discussed along with some examples of successful applications. Sol-gel derived metal oxide electrode materials such as V2O5 cathodes have been demonstrated in solid-slate thin film batteries; solid electrolytes materials such as beta-alumina for advanced secondary batteries had been prepared by the sol-gel technique long time ago; and high surface area transition metal compounds for capacitive energy storage applications can also be synthesized with this method.

  11. Electrical silencing of PDF neurons advances the phase of non-PDF clock neurons in Drosophila.

    PubMed

    Wu, Ying; Cao, Guan; Nitabach, Michael N

    2008-04-01

    Drosophila clock neurons exhibit self-sustaining cellular oscillations that rely in part on rhythmic transcriptional feedback loops. We have previously determined that electrical silencing of the pigment dispersing factor (PDF)-expressing lateral-ventral (LN(V)) pacemaker subset of fly clock neurons via expression of an inward-rectifier K(+) channel (Kir2.1) severely disrupts free-running rhythms of locomotor activity-most flies are arrhythmic and those that are not exhibit weak short-period rhythms-and abolishes LN(V) molecular oscillation in constant darkness. PDF is known to be an important LN(V) output signal. Here we examine the effects of electrical silencing of the LN(V) pacemakers on molecular rhythms in other, nonsilenced, subsets of clock neurons. In contrast to previously described cell-autonomous abolition of free-running molecular rhythms, we find that electrical silencing of the LN(V) pacemakers via Kir2.1 expression does not impair molecular rhythms in LN(D), DN1, and DN2 subsets of clock neurons. However, free-running molecular rhythms in these non-LN(V) clock neurons occur with advanced phase. Electrical silencing of LN(V)s phenocopies PDF null mutation (pdf (01) ) at both behavioral and molecular levels except for the complete abolition of free-running cellular oscillation in the LN(V)s themselves. LN(V) electrically silenced or pdf 01 flies exhibit weak free-running behavioral rhythms with short period, and the molecular oscillation in non-LN(V) neurons phase advances in constant darkness. That LN( V) electrical silencing leads to the same behavioral and non-LN( V) molecular phenotypes as pdf 01 suggests that persistence of LN(V) molecular oscillation in pdf 01 flies has no functional effect, either on behavioral rhythms or on non-LN(V) molecular rhythms. We thus conclude that functionally relevant signals from LN(V)s to non-LN(V) clock neurons and other downstream targets rely both on PDF signaling and LN(V) electrical activity, and that LN( V

  12. Advanced materials for improved PEMFC performance and life

    NASA Astrophysics Data System (ADS)

    Curtin, Dennis E.; Lousenberg, Robert D.; Henry, Timothy J.; Tangeman, Paul C.; Tisack, Monica E.

    Physical and functional attributes are reviewed for recently developed Nafion ® products that satisfy emerging fuel cell requirements—including stronger, more durable membranes, and polymer dispersions of higher quality and consistency for catalyst inks and film formation. Size exclusion chromatography (SEC) analysis has confirmed that dispersion viscosity is related to an "apparent" molar mass, resulting from a molecular aggregate structure. Membranes produced with solution-casting and advanced extrusion technologies exhibit improved water management and mechanical durability features, respectively. Additionally, DuPont has shown that experimentally modified Nafion ® polymer exhibits 56% reduction in fluoride ion generation, which is considered a measure of membrane lifetime.

  13. Advanced computational research in materials processing for design and manufacturing

    SciTech Connect

    Zacharia, T.

    1994-12-31

    The computational requirements for design and manufacture of automotive components have seen dramatic increases for producing automobiles with three times the mileage. Automotive component design systems are becoming increasingly reliant on structural analysis requiring both overall larger analysis and more complex analyses, more three-dimensional analyses, larger model sizes, and routine consideration of transient and non-linear effects. Such analyses must be performed rapidly to minimize delays in the design and development process, which drives the need for parallel computing. This paper briefly describes advanced computational research in superplastic forming and automotive crash worthiness.

  14. Materials issues in some advanced forming techniques, including superplasticity

    SciTech Connect

    Wadsworth, J.; Henshall, G.A.; Nieh, T.G.

    1995-08-22

    From mechanics and macroscopic viewpoints, the sensitivity of the flow stress of a material to the strain rate, i.e. the strain rate sensitivity (m), governs the development of neck formation and therefore has a strong influence on the tensile ductility and hence formability of materials. Values of strain rate sensitivity range from unity, for the case of Newtonian viscous materials, to less than 0.1 for some dispersion strengthened alloys. Intermediate values of m = 0.5 are associated with classical superplastic materials which contain very fine grain sizes following specialized processing. An overview is given of the influence of strain rate sensitivity on tensile ductility and of the various materials groups that can exhibit high values of strain rate sensitivity. Recent examples of enhanced formability (or extended tensile ductility) in specific regimes between m = 1 and m = 0.3 are described, and potential areas for commercial exploitation are noted. These examples include: internal stress superplasticity, superplastic ceramics, superplastic intermetallics, superplastic laminated composites, superplastic behavior over six orders of magnitude of strain rate in a range of aluminum-based alloys and composites, and enhanced ductility in Al-Mg alloys that require no special processing for microstructural development.

  15. Advancing Materials Science using Neutrons at Oak Ridge National Laboratory

    ScienceCinema

    Carpenter, John

    2014-06-03

    Jack Carpenter, pioneer of accelerator-based pulsed spallation neutron sources, talks about neutron science at Oak Ridge National Laboratory (ORNL) and a need for a second target station at the Spallation Neutron Source (SNS). ORNL is the Department of Energy's largest multiprogram science and energy laboratory, and is home to two scientific user facilities serving the neutron science research community: the High Flux Isotope Reactor (HFIR) and SNS. HFIR and SNS provide researchers with unmatched capabilities for understanding the structure and properties of materials, macromolecular and biological systems, and the fundamental physics of the neutron. Neutrons provide a window through which to view materials at a microscopic level that allow researchers to develop better materials and better products. Neutrons enable us to understand materials we use in everyday life. Carpenter explains the need for another station to produce long wavelength neutrons, or cold neutrons, to answer questions that are addressed only with cold neutrons. The second target station is optimized for that purpose. Modern technology depends more and more upon intimate atomic knowledge of materials, and neutrons are an ideal probe.

  16. Advancing Materials Science using Neutrons at Oak Ridge National Laboratory

    SciTech Connect

    Carpenter, John

    2014-04-24

    Jack Carpenter, pioneer of accelerator-based pulsed spallation neutron sources, talks about neutron science at Oak Ridge National Laboratory (ORNL) and a need for a second target station at the Spallation Neutron Source (SNS). ORNL is the Department of Energy's largest multiprogram science and energy laboratory, and is home to two scientific user facilities serving the neutron science research community: the High Flux Isotope Reactor (HFIR) and SNS. HFIR and SNS provide researchers with unmatched capabilities for understanding the structure and properties of materials, macromolecular and biological systems, and the fundamental physics of the neutron. Neutrons provide a window through which to view materials at a microscopic level that allow researchers to develop better materials and better products. Neutrons enable us to understand materials we use in everyday life. Carpenter explains the need for another station to produce long wavelength neutrons, or cold neutrons, to answer questions that are addressed only with cold neutrons. The second target station is optimized for that purpose. Modern technology depends more and more upon intimate atomic knowledge of materials, and neutrons are an ideal probe.

  17. Novel Super-Elastic Materials for Advanced Bearing Applications

    NASA Technical Reports Server (NTRS)

    Dellacorte, Christopher

    2014-01-01

    Tribological surfaces of mechanical components encounter harsh conditions in terrestrial, marine and aerospace environments. Brinell denting, abrasive wear and fatigue often lead to life-limiting bearing and gear failures. Novel superelastic materials based upon Ni-Ti alloys are an emerging solution. Ni-Ti alloys are intermetallic materials that possess characteristics of both metals and ceramics. Ni-Ti alloys have intrinsically good aqueous corrosion resistance (they cannot rust), high hardness, relatively low elastic modulus, are chemically inert and readily lubricated. Ni-Ti alloys also belong to the family of superelastics and, despite high hardness, are able to withstand large strains without suffering permanent plastic deformation. In this paper, the use of hard, resilient Ni-Ti alloys for corrosion-proof, shockproof bearing and gear applications are presented. Through a series of bearing and gear development projects, it is demonstrated that Ni-Tis unique blend of materials properties lead to significantly improved load capacity, reduced weight and intrinsic corrosion resistance not found in any other bearing materials. Ni-Ti thus represents a new materials solution to demanding tribological applications.

  18. Development of Processing Techniques for Advanced Thermal Protection Materials

    NASA Technical Reports Server (NTRS)

    Selvaduray, Guna; Cox, Michael; Srinivasan, Vijayakumar

    1997-01-01

    Thermal Protection Materials Branch (TPMB) has been involved in various research programs to improve the properties and structural integrity of the existing aerospace high temperature materials. Specimens from various research programs were brought into the analytical laboratory for the purpose of obtaining and refining the material characterization. The analytical laboratory in TPMB has many different instruments which were utilized to determine the physical and chemical characteristics of materials. Some of the instruments that were utilized by the SJSU students are: Scanning Electron Microscopy (SEM), Energy Dispersive X-ray analysis (EDX), X-ray Diffraction Spectrometer (XRD), Fourier Transform-Infrared Spectroscopy (FTIR), Ultra Violet Spectroscopy/Visible Spectroscopy (UV/VIS), Particle Size Analyzer (PSA), and Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES). The above mentioned analytical instruments were utilized in the material characterization process of the specimens from research programs such as: aerogel ceramics (I) and (II), X-33 Blankets, ARC-Jet specimens, QUICFIX specimens and gas permeability of lightweight ceramic ablators. In addition to analytical instruments in the analytical laboratory at TPMB, there are several on-going experiments. One particular experiment allows the measurement of permeability of ceramic ablators. From these measurements, physical characteristics of the ceramic ablators can be derived.

  19. Advanced ceramic material for high temperature turbine tip seals

    NASA Technical Reports Server (NTRS)

    Solomon, N. G.; Vogan, J. W.

    1978-01-01

    Ceramic material systems are being considered for potential use as turbine blade tip gas path seals at temperatures up to 1370 1/4 C. Silicon carbide and silicon nitride structures were selected for study since an initial analysis of the problem gave these materials the greatest potential for development into a successful materials system. Segments of silicon nitride and silicon carbide materials over a range of densities, processed by various methods, a honeycomb structure of silicon nitride and ceramic blade tip inserts fabricated from both materials by hot pressing were tested singly and in combination. The evaluations included wear under simulated engine blade tip rub conditions, thermal stability, impact resistance, machinability, hot gas erosion and feasibility of fabrication into engine components. The silicon nitride honeycomb and low-density silicon carbide using a selected grain size distribution gave the most promising results as rub-tolerant shroud liners. Ceramic blade tip inserts made from hot-pressed silicon nitride gave excellent test results. Their behavior closely simulated metal tips. Wear was similar to that of metals but reduced by a factor of six.

  20. FY2013 Advanced Power Electronics and Electric Motors R&D Annual Progress Report

    SciTech Connect

    Rogers, Susan A.

    2014-02-01

    The Advanced Power Electronics and Electric Motors (APEEM) technology area within the DOE Vehicle Technologies Office (VTO) provides support and guidance for many cutting-edge automotive technologies now under development. Research is focused on developing revolutionary new power electronics (PE), electric motor, and traction drive system (TDS) technologies that will leapfrog current on-the-road technologies, leading to lower cost and better efficiency in transforming battery energy to useful work. The research and development (R&D) is also aimed at achieving a greater understanding of and improvements in the way the various new components of tomorrow’s automobiles will function as a unified system to improve fuel efficiency through research in more efficient TDSs.

  1. Performance and life evaluation of advanced battery technologies for electric vehicle applications

    SciTech Connect

    DeLuca, W.H.; Gillie, K.R.; Kulaga, J.E.; Smaga, J.A.; Tummillo, A.F.; Webster, C.E.

    1991-01-01

    Advanced battery technology evaluations are performed under simulated electric vehicle (EV) operating conditions at the Argonne Analysis Diagnostic Laboratory (ADL). The ADL provides a common basis for both performance characterization and life evaluation with unbiased application of tests and analyses. This paper summarizes the performance characterizations and life evaluations conducted in 1990 on nine single cells and fifteen 3- to 360-cell modules that encompass six technologies (Na/S, Zn/Br, Ni/Fe, Ni/Cd, Ni-metal hydride, and lead-acid). These evaluations were performed for the Department of Energy and Electric Power Research Institute. The results provide battery users, developers, and program managers an interim measure of the progress being made in battery R D programs, a comparison of battery technologies, and a source of basic data for modelling and continuing R D. 1 ref., 4 figs., 2 tabs.

  2. Performance and life evaluation of advanced battery technologies for electric vehicle applications

    NASA Astrophysics Data System (ADS)

    Deluca, W. H.; Gillie, K. R.; Kulaga, J. E.; Smaga, J. A.; Tummillo, A. F.; Webster, C. E.

    Advanced battery technology evaluations are performed under simulated electric vehicle (EV) operating conditions at the Argonne Analysis and Diagnostic Laboratory (ADL). The ADL provides a common basis for both performance characterization and life evaluation with unbiased application of tests and analyses. This paper summarizes the performance characterizations and life evaluations conducted in 1990 on nine single cells and fifteen 3- to 360-cell modules that encompass six technologies: (Na/S, Zn/Br, Ni/Fe, Ni/Cd, Ni-metal hydride, and lead-acid). These evaluations were performed for the Department of Energy and Electric Power Research Institute. The results provide battery users, developers, and program managers an interim measure of the progress being made in battery R and D programs, a comparison of battery technologies, and a source of basic data for modelling and continuing R and D.

  3. Advanced Process Technology: Combi Materials Science and Atmospheric Processing (Fact Sheet)

    SciTech Connect

    Not Available

    2011-06-01

    Capabilities fact sheet for the National Center for Photovoltaics: Process Technology and Advanced Concepts -- High-Throughput Combi Material Science and Atmospheric Processing that includes scope, core competencies and capabilities, and contact/web information.

  4. River Devices to Recover Energy with Advanced Materials (River DREAM)

    SciTech Connect

    McMahon, Daniel P.

    2013-07-03

    The purpose of this project is to develop a generator called a Galloping Hydroelectric Energy Extraction Device (GHEED). It uses a galloping prism to convert water flow into linear motion. This motion is converted into electricity via a dielectric elastomer generator (DEG). The galloping mechanism and the DEG are combined to create a system to effectively generate electricity. This project has three research objectives: 1. Oscillator development and design a. Characterize galloping behavior, evaluate control surface shape change on oscillator performance and demonstrate shape change with water flow change. 2. Dielectric Energy Generator (DEG) characterization and modeling a. Characterize and model the performance of the DEG based on oscillator design 3. Galloping Hydroelectric Energy Extraction Device (GHEED) system modeling and integration a. Create numerical models for construction of a system performance model and define operating capabilities for this approach Accomplishing these three objectives will result in the creation of a model that can be used to fully define the operating parameters and performance capabilities of a generator based on the GHEED design. This information will be used in the next phase of product development, the creation of an integrated laboratory scale generator to confirm model predictions.

  5. Materials issues for advanced electronic and optoelectronic connectors

    NASA Astrophysics Data System (ADS)

    Crane, J.; Wen, S.

    1990-09-01

    Trends of increased speed, density and power of electronic devices and circuitry translate to a need for connector substrate materials with improved form-ability and mechanical stability. Many contact surface requirements will continue to be met by precious metals for low contact force and tin in moderate contact force connectors. However, the demands for lower insertion forces, increased wear resistance, higher operating temperatures and improved corrosion resistance will challenge materials experts and connector designers to develop and utilize cost-effective replacements for tin and gold in electronic connectors. The stability and compatibility requirements of optoelectronic connectors provide challenges over a wide range of materials with the added dimension of accommodating essential optical characteristics.

  6. Development of processing techniques for advanced thermal protection materials

    NASA Technical Reports Server (NTRS)

    Selvaduray, Guna S.

    1995-01-01

    The main purpose of this work has been in the development and characterization of materials for high temperature applications. Thermal Protection Systems (TPS) are constantly being tested, and evaluated for increased thermal shock resistance, high temperature dimensional stability, and tolerance to environmental effects. Materials development was carried out through the use of many different instruments and methods, ranging from extensive elemental analysis to physical attributes testing. The six main focus areas include: (1) protective coatings for carbon/carbon composites; (2) TPS material characterization; (3) improved waterproofing for TPS; (4) modified ceramic insulation for bone implants; (5) improved durability ceramic insulation blankets; and (6) ultra-high temperature ceramics. This report describes the progress made in these research areas during this contract period.

  7. Advanced Strain-Isolation-Pad Material with Bonded Fibrous Construction

    NASA Technical Reports Server (NTRS)

    Seibold, R. W.; Saito, C. A.; Buller, B. W.

    1982-01-01

    The feasibility of utilizing air lay and liquid lay felt deposition techniques to fabricate strain isolation pad (SIP) materials for the Space Shuttle Orbiter was demonstrated. These materials were developed as candidate replacements for the present needled felt SIP used between the ceramic tiles and the aluminum skin on the undersurface of the Orbiter. The SIP materials that were developed consisted of high temperature aramid fibers deposited by controlled fluid (air or liquid) carriers to form low density unbonded felts. The deposited felts were then bonded at the fiber intersections with a small amount of high temperature polyimide resin. This type of bonded felt construction can potentially eliminate two of the problems associated with the present SIP, viz., transmittal of localized stresses into the tiles and load history dependent mechanical response. However, further work is needed to achieve adequate through thickness tensile strength in the bonded felts.

  8. Advanced materials development for multi-junction monolithic photovoltaic devices

    SciTech Connect

    Dawson, L.R.; Reno, J.L.

    1996-07-01

    We report results in three areas of research relevant to the fabrication of monolithic multi-junction photovoltaic devices. (1) The use of compliant intervening layers grown between highly mismatched materials, GaAs and GaP (same lattice constant as Si), is shown to increase the structural quality of the GaAs overgrowth. (2) The use of digital alloys applied to the MBE growth of GaAs{sub x}Sb{sub l-x} (a candidate material for a two junction solar cell) provides increased control of the alloy composition without degrading the optical properties. (3) A nitrogen plasma discharge is shown to be an excellent p-type doping source for CdTe and ZnTe, both of which are candidate materials for a two junction solar cell.

  9. Recent Advances and Developments in Composite Dental Restorative Materials

    PubMed Central

    Cramer, N.B.; Stansbury, J.W.; Bowman, C.N.

    2011-01-01

    Composite dental restorations represent a unique class of biomaterials with severe restrictions on biocompatibility, curing behavior, esthetics, and ultimate material properties. These materials are presently limited by shrinkage and polymerization-induced shrinkage stress, limited toughness, the presence of unreacted monomer that remains following the polymerization, and several other factors. Fortunately, these materials have been the focus of a great deal of research in recent years with the goal of improving restoration performance by changing the initiation system, monomers, and fillers and their coupling agents, and by developing novel polymerization strategies. Here, we review the general characteristics of the polymerization reaction and recent approaches that have been taken to improve composite restorative performance. PMID:20924063

  10. Progress on advanced dc and ac induction drives for electric vehicles

    NASA Technical Reports Server (NTRS)

    Schwartz, H. J.

    1982-01-01

    Progress is reported in the development of complete electric vehicle propulsion systems, and the results of tests on the Road Load Simulator of two such systems representative of advanced dc and ac drive technology are presented. One is the system used in the DOE's ETV-1 integrated test vehicle which consists of a shunt wound dc traction motor under microprocessor control using a transistorized controller. The motor drives the vehicle through a fixed ratio transmission. The second system uses an ac induction motor controlled by transistorized pulse width modulated inverter which drives through a two speed automatically shifted transmission. The inverter and transmission both operate under the control of a microprocessor. The characteristics of these systems are also compared with the propulsion system technology available in vehicles being manufactured at the inception of the DOE program and with an advanced, highly integrated propulsion system upon which technology development was recently initiated.

  11. Analysis of life cycle costs for electric vans with advanced battery systems

    SciTech Connect

    Marr, W.W.; Walsh, W.J.; Miller, J.F.

    1988-11-01

    The performance of advanced Zn/Br/sub 2/, LiAl/FeS, Na/S, Ni/Fe, and Fe/Air batteries in electric vans was compared to that of tubular lead-acid technology. The MARVEL computer analysis system evaluated these batteries for the G-Van and IDSEP vehicles over two driving schedules. Each of the advanced batteries exhibited the potential for major improvements in both range and life cycle cost compared with tubular lead-acid. A sensitivity analysis revealed specific energy, battery initial cost, and cycle life to be the dominant factors in reducing life cycle cost for the case of vans powered by tubular lead-acid batteries. 5 refs., 8 figs., 2 tabs.

  12. Analysis of life cycle costs for electric vans with advanced battery systems

    SciTech Connect

    Marr, W.W.; Walsh, W.J.; Miller, J.F.

    1989-01-01

    The performance of advanced Zn/Br/sub 2/, LiAl/FeS, Na/S, Ni/Fe, and Fe/Air batteries in electric vans was compared to that of tubular lead-acid technology. The MARVEL computer analysis system evaluated these batteries for the G-Van and IDSEP vehicles over two driving schedules. Each of the advanced batteries exhibited the potential for major improvements in both range and life cycle cost compared with tubular lead-acid. A sensitivity analysis reveals specific energy, battery initial cost, and cycle life to be the dominant factors in reducing life cycle cost for the case of vans powered by tubular lead-acid batteries.

  13. Advanced launch system (ALS) - Electrical actuation and power systems improve operability and cost picture

    NASA Technical Reports Server (NTRS)

    Sundberg, Gale R.

    1990-01-01

    To obtain the Advanced Launch System (ALS) primary goals of reduced costs and improved operability, there must be significant reductions in the launch operations and servicing requirements relative to current vehicle designs and practices. One of the primary methods for achieving these goals is by using vehicle electrrical power system and controls for all aviation and avionics requirements. A brief status review of the ALS and its associated Advanced Development Program is presented to demonstrate maturation of those technologies that will help meet the overall operability and cost goals. The electric power and actuation systems are highlighted as a sdpecific technology ready not only to meet the stringent ALS goals (cryogenic field valves and thrust vector controls with peak power demands to 75 hp), but also those of other launch vehicles, military ans civilian aircraft, lunar/Martian vehicles, and a multitude of comercial applications.

  14. Kuiper Belt Object Orbiter Using Advanced Radioisotope Power Sources and Electric Propulsion

    NASA Technical Reports Server (NTRS)

    Oleson, Steven R.; McGuire, Melissa L.; Dankanich, John; Colozza, Anthony; Schmitz, Paul; Khan, Omair; Drexler, Jon; Fittje, James

    2011-01-01

    A joint NASA GRC/JPL design study was performed for the NASA Radioisotope Power Systems Office to explore the use of radioisotope electric propulsion for flagship class missions. The Kuiper Belt Object Orbiter is a flagship class mission concept projected for launch in the 2030 timeframe. Due to the large size of a flagship class science mission larger radioisotope power system building blocks were conceptualized to provide the roughly 4 kW of power needed by the NEXT ion propulsion system and the spacecraft. Using REP the spacecraft is able to rendezvous with and orbit a Kuiper Belt object in 16 years using either eleven (no spare) 420 W advanced RTGs or nine (with a spare) 550 W advanced Stirling Radioisotope systems. The design study evaluated integrating either system and estimated impacts on cost as well as required General Purpose Heat Source requirements.

  15. Nanostructured Materials for Advanced Electrochemical Energy Storage Applications

    NASA Astrophysics Data System (ADS)

    Wilson, Benjamin E.

    This dissertation discusses work aimed at developing and improving nanostructured materials for electrochemical energy storage, specifically electrochemical double layer capacitors (EDLCs) and lithium-ion batteries (LIBs). This was achieved through a combination of templating, precursor selection, and heteroatom doping to control the morphology and composition of the materials for improved performance in both types of energy storage. The first part of the thesis discusses EDLCs. First, a new method to produce soft-templated carbon materials is described. This process allows for improved production of mesoporous carbon made through soft templating. The work continues with using ionic liquids to dope nitrogen into hard templated mesoporous carbon. This led to a 40% improvement in specific capacitance due to improved conductivity. The section concludes with an investigation of physical and electrochemical properties of twelve ionic liquid electrolytes to determine which parameters are most important to achieve a high energy density. The second part discusses my work on LIBs, starting with a design of a low-cost electrochemical cell for in-situ X-ray diffraction monitoring during galvanostatic cycling. It continues with the development of a novel cathode material, Li8ZrO6, with a high lithium content. In this material, the redox activity is localized on oxygen atoms. Li8ZrO6 displays initial capacities higher than those of commercial materials but has large polarization. The capacity is further improved with transition metal doping, leading to a final specific capacity of over 175 mAh/g after 140 cycles at a rate of C/5.

  16. Advanced risk assessment of the effects of graphite fibers on electronic and electric equipment

    NASA Technical Reports Server (NTRS)

    Pocinki, L.; Cornell, M.; Kaplan, L.

    1980-01-01

    An assessment of the risk associated with accidents involving aircraft with carbon fiber composite structural components is examined. The individual fiber segments cause electrical and electronic equipment to fail under certain operating conditions. A Monte Carlo simulation model was used to computer the risk. Aircraft accidents with fire, release of carbon fiber material, entrainment of carbon fibers in a smoke plume transport of fibers downwind, transfer of some fibers/into the the interior of buildings, failures of electrical and electronic equipment, and economic impact of failures are discussed. Risk profiles were prepared for individual airports and the Nation. The vulnerability of electrical transmission equipment to carbon fiber incursion and aircraft accident total costs is investigated.

  17. The effects of regional insolation differences upon advanced solar thermal electric power plant performance and energy costs

    NASA Technical Reports Server (NTRS)

    Latta, A. F.; Bowyer, J. M.; Fujita, T.; Richter, P. H.

    1979-01-01

    The performance and cost of the 10 MWe advanced solar thermal electric power plants sited in various regions of the continental United States were determined. The regional insolation data base is discussed. A range for the forecast cost of conventional electricity by region and nationally over the next several cades are presented.

  18. Advanced computer techniques for inverse modeling of electric current in cardiac tissue

    SciTech Connect

    Hutchinson, S.A.; Romero, L.A.; Diegert, C.F.

    1996-08-01

    For many years, ECG`s and vector cardiograms have been the tools of choice for non-invasive diagnosis of cardiac conduction problems, such as found in reentrant tachycardia or Wolff-Parkinson-White (WPW) syndrome. Through skillful analysis of these skin-surface measurements of cardiac generated electric currents, a physician can deduce the general location of heart conduction irregularities. Using a combination of high-fidelity geometry modeling, advanced mathematical algorithms and massively parallel computing, Sandia`s approach would provide much more accurate information and thus allow the physician to pinpoint the source of an arrhythmia or abnormal conduction pathway.

  19. Development of electrical feedback controlled heat pipes and the advanced thermal control flight experiment

    NASA Technical Reports Server (NTRS)

    Bienert, W. B.

    1974-01-01

    The development and characteristics of electrical feedback controlled heat pipes (FCHP) are discussed. An analytical model was produced to describe the performance of the FCHP under steady state and transient conditions. An advanced thermal control flight experiment was designed to demonstrate the performance of the thermal control component in a space environment. The thermal control equipment was evaluated on the ATS-F satellite to provide performance data for the components and to act as a thermal control system which can be used to provide temperature stability of spacecraft components in future applications.

  20. Advances in optical property measurements of spacecraft materials

    NASA Technical Reports Server (NTRS)

    Smith, Charles A.; Dever, Joyce A.; Jaworske, Donald A.

    1997-01-01

    Some of the instruments and experimental approaches, used for measuring the optical properties of thermal control systems, are presented. The instruments' use in studies concerning the effects of combined contaminants and space environment on these materials, and in the qualification of hardware for spacecraft, are described. Instruments for measuring the solar absorptance and infrared emittance offer improved speed, accuracy and data handling. A transient method for directly measuring material infrared emittance is described. It is shown that oxygen exposure before measuring the solar absorptance should be avoided.